한국 다이빙 오기: 외국인 다이버 종합 가이드

!30-bases/regions.base

last_verified: "2026-06-27" Domain 08 — Foreign Diver Logistics. Audience: international divers planning a dive trip to South Korea. Every factual claim below carries a source and a verification level. Entry/visa, airport, KTX and ferry facts are drawn from official sources; travel tips (eSIM, payment, gear) are aggregated unless noted. Region "Getting there" sections synthesize the project's own data/regions/*.yaml (status: verified). Where rules change by nationality or by season, the text says verify with official source rather than asserting a single value.

한글 요약: 이 문서는 외국인 다이버가 한국에 와서 다이빙하기까지의 전 동선(입국·공항·권역 이동·통신·결제·언어·장비·셀링포인트)을 영문 중심으로 정리한 가이드입니다. 입국/교통은 공식 출처, 여행 팁은 집계 출처 기준이며, 국적·시즌별로 달라지는 항목은 단정하지 않고 "공식 확인 필요"로 표기했습니다.

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1. Overview (개요)

South Korea is a four-season dive destination that remains largely undiscovered by foreign divers, even though its best sites rival far more famous regions. The country's dive areas split into five regions: Jeju (제주) — volcanic islets with world-class soft coral; East Sea / 동해 — wrecks, offshore shoals and cold-water macro within 2–3 hours of Seoul; South Sea / 남해 — warm-water island boat diving; Ulleungdo & Dokdo / 울릉도·독도 — Korea's clearest water in the far East Sea; and the West Sea / 서해 (Yellow Sea) — tide-driven, expert-only offshore islets.

For a foreign diver the practical reality is: Jeju and Busan (a South Sea gateway) are the most foreigner-ready; everywhere else, English support is limited and advance booking with a translation app is strongly advised (see §8). Entry is straightforward for most Western and East Asian nationalities thanks to a K-ETA waiver extended through end-2026, plus Jeju's separate visa-free zone.

한글 요약: 한국은 사계절 다이빙이 가능하지만 외국인에게는 아직 덜 알려진 목적지입니다. 권역은 제주·동해·남해·울릉도독도·서해 5개이며, 외국인 응대가 가장 잘 되는 곳은 제주와 부산(남해 관문)입니다. 그 외 권역은 영어 지원이 제한적이라 사전 예약과 번역 앱 사용을 권장합니다.

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2. Entry & Visa (입국·비자)

All entry rules below are nationality-dependent and change periodically. Always re-check the official portals (k-eta.go.kr, e-arrivalcard.go.kr, hikorea.go.kr) before booking. [level: official / verify needed for your nationality]

2.1 K-ETA waiver extended through 31 December 2026

South Korea has extended the temporary K-ETA (Korea Electronic Travel Authorization) exemption to 31 December 2026 for nationals of 22 designated countries/territories: Australia, Austria, Belgium, Canada, Denmark, Finland, France, Germany, Hong Kong, Italy, Japan, Macao, Netherlands, New Zealand, Norway, Poland, Singapore, Spain, Sweden, Taiwan, the United Kingdom, and the United States (incl. Guam). Nationals of these places visiting for tourism/short-term business (typically up to 90 days) do not need to apply for K-ETA. [Fragomen / Erickson Immigration Group / VisitKorea — official + primary]

• Travelers not on this 22-country list but otherwise visa-exempt generally must hold a valid K-ETA, applied for online at k-eta.go.kr (small fee; apply well before departure). Exact fee, validity and eligible-country list must be verified on the official K-ETA site — they change. [level: official / verify needed]
• Holding a K-ETA is optional-but-useful even for waiver nationals: an approved K-ETA exempts you from filing the arrival card (see below). [VisitKorea — official]

2.2 e-Arrival Card is now mandatory (mandatory from 1 Jan 2026)

Paper arrival cards have been abolished. From 1 January 2026 the digital e-Arrival Card is mandatory for all foreign visitors who do NOT hold a valid K-ETA. File it free at the only official portal, www.e-arrivalcard.go.kr, within 72 hours before arrival; save the QR code to show at immigration. Even K-ETA-waiver nationals (US, UK, Japan, etc.) must file the e-Arrival Card unless they voluntarily obtained a K-ETA. Beware third-party sites that charge a fee — they are scams. [VisitKorea / multiple aggregated guides — official portal confirmed]

2.3 Jeju's separate visa-free zone (제주 무사증)

Jeju operates a special visa-free program independent of mainland visa rules: most nationalities (100+) may enter visa-free for up to 30 days when arriving on a direct international flight/ship to Jeju (CJU airport or Jeju seaports) for tourism — but you must stay only on Jeju. Roughly 23 nationalities are excluded (e.g., several South/Central Asian and Middle Eastern states; lists shift). If you plan to dive elsewhere in Korea too, you fall under standard national visa/K-ETA rules instead. Verify your nationality on the official MOFA / Jeju immigration notice. [MOFA Singapore Embassy notice — official; Wikipedia visa policy — primary]

한글 요약: (1) 미국·일본·영국 등 22개국·지역은 2026-12-31까지 K-ETA 면제(관광·단기상용 무비자 입국). 그 외 무비자 국적은 대체로 K-ETA 필요(k-eta.go.kr, 출발 전 발급). (2) 2026-01-01부터 종이 입국카드 폐지, K-ETA 미소지자는 e-Arrival Card(e-arrivalcard.go.kr, 무료, 도착 72시간 전 작성) 의무. 유료 사이트는 사기. (3) 제주는 별도 무사증 — 직항으로 제주 입도 시 대부분 국적 30일 무비자(제주 내에서만 체류), 약 23개국 제외. 모두 국적별로 다르므로 공식 확인 필수.

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3. Airport Gateways (항공 게이트웨이)

Most international divers land at ICN, then either take a domestic flight (often from Gimpo/GMP) or KTX/intercity bus to the dive region. Jeju-bound divers can fly direct internationally to CJU (and use the Jeju visa-free entry). [Region YAML gateways — verified; airport roles — aggregated/official]

한글 요약: 외국인 대부분은 인천(ICN) 입국 후 국내선(주로 김포 GMP) 또는 KTX·버스로 권역 이동. 제주는 해외 직항으로 제주공항(CJU) 직접 입국 가능(무사증). 부산 김해(PUS)는 남해 관문, 양양(YNY)은 동해, 여수(RSU)·사천(HIN)은 남해, 군산(KUV)은 서해와 연계.

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4. Getting to Each Region (권역별 이동 동선)

Synthesized from data/regions/*.yaml (access.gateways / from_seoul / from_abroad, status: verified). Times are approximate and weather/schedule-dependent.

4.1 Jeju (제주) — easiest for foreigners

• Direct: International direct flight to Jeju (CJU) under the 30-day Jeju visa-free program (direct arrivals only; stay on Jeju only). Then ~1 h drive from Jeju Airport to Seogwipo, and board the dive boat at Seogwipo Port — the islets Munseom · Beomseom · Seopseom are ~5 minutes out.
• Via mainland: Arrive ICN/GMP, transfer to a domestic flight to Jeju (~1 h from Seoul-Gimpo). Standard Korea entry rules apply on this route.
• Why it's the easy choice: highest concentration of English-capable shops in Korea (see §8).

4.2 East Sea / 동해 (Goseong · Yangyang · Sokcho · Gangneung · Uljin)

• From ICN → AREX/limousine to Seoul Station → KTX to Gangneung (~2 h), then car/bus to Goseong/Yangyang/Uljin. Alternatively, direct intercity buses run from Incheon Airport to Gangneung/Sokcho.
• Boat-diving ports: Ayajin (Goseong), Ingu (Yangyang), Sacheon (Gangneung), Hupo/Gusan (Uljin).
• Closest airport is Yangyang (YNY) but international service is limited. Realistically a 2–3 h trip from Seoul — very doable, but local English support is thin (book ahead, see §8).

4.3 South Sea / 남해 (Yeosu · Tongyeong · Geoje · Namhae · Busan)

• Yeosu: from ICN, go to Seoul/Yongsan and take the Jeolla-line KTX to Yeosu-EXPO (~3 h), or fly Gimpo→Yeosu (RSU). Islands like Geomundo need an onward ferry from Yeosu Coastal Ferry Terminal.
• Tongyeong / Namhae / Geoje: fly Gimpo/Incheon→Sacheon (HIN) then bus, or KTX to Jinju/Suncheon then intercity bus.
• Busan (a practical SE gateway): international flights into Gimhae (PUS); Busan hosts several English-capable dive operators.

4.4 West Sea / 서해 (Yellow Sea) — expert-only, hardest logistics

• Arrive ICN, travel overland to the West Sea coast (Taean/Boryeong/Gunsan). Offshore islet points (e.g., Gyeokryeolbiyeoldo, Sibidongpado) have no scheduled ferry — a chartered boat is required, and safe diving is limited to slack tide on small-tidal-range days.
• No English-speaking local dive shop is confirmed in the project data; trips are usually run by capital-region clubs on charter boats. Arrange bookings and interpretation far in advance. Best suited to experienced divers, not first-time visitors.

4.5 Ulleungdo & Dokdo / 울릉도·독도 — Korea's clearest water, remote

• From ICN/GMP → KTX/bus to a mainland ferry port (Pohang, Gangneung, Donghae/Mukho, Hupo) → passenger ferry to Ulleungdo (~3–3.5 h). No operating airport yet (Ulleung Airport under construction — re-verify on opening).
• Dokdo requires a further ferry + entry permit (apply ≥14 days ahead); landing is possible only when swell ≤3–5 m (on average ~once every 40 days). Frequent weather cancellations — build buffer days.
• Pays off with ~20–30 m visibility year-round (up to 40–50 m seasonally) — the best in Korea.

한글 요약: 제주가 외국인에게 가장 쉬움(직항 입국·영어 샵 다수). 동해는 인천→KTX 강릉 약 2시간 또는 인천공항 직행버스, 항구는 아야진·인구·사천·후포. 남해 여수는 KTX 여수EXPO 약 3시간(거문도는 추가 여객선), 통영·남해·거제는 사천공항/진주 KTX 후 버스, 부산은 김해공항 관문. 서해는 정기 여객선 없는 전세선·정조 한정·영어 샵 미확인으로 숙련자 전용. 울릉도독도는 육지 항구→여객선 3~3.5시간, 독도는 입도허가(14일 전)·기상 변수 큼.

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5. Connectivity — eSIM & SIM (통신: eSIM·유심) [level: aggregated]

• eSIM (recommended). If your phone supports eSIM (most 2020+ flagships), buy online before departure and activate on landing — no airport queue. Providers seen in 2026 guides: Airalo, Saily, Holafly, esim Korea, Gohub (plans roughly from a few USD for a few days up to ~$47/30-day unlimited). [aggregated]
• Physical SIM at Incheon (ICN). Counters for KT, SK Telecom, LG U+ are in Terminal 1 between exits 6–7 and 10–11, and in Terminal 2 between exits 4–5. Pre-ordering online (e.g., LG U+) and picking up at the airport is usually cheaper than the walk-up counter; the SIM holder often doubles as a T-money transit card. [aggregated]
• Pocket WiFi (WiFi egg/router) is also rentable at airports for groups.
• Diver's note: coastal/island dive areas (East Sea ports, Ulleungdo, West Sea islets) can have patchy coverage offshore — download offline maps and your translation app before heading out.

한글 요약: eSIM은 출발 전 온라인 구매 후 도착 즉시 활성화가 가장 편함(Airalo·Holafly·esim Korea 등). 인천공항 KT/SKT/LG U+ 카운터에서 실물 유심도 가능(T1 6–7·10–11번 출구, T2 4–5번 출구). 도서·연안 다이빙지는 해상 통신이 약할 수 있어 오프라인 지도/번역앱 미리 준비.

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6. Payment (결제) [level: aggregated]

• Cards work almost everywhere. Visa/Mastercard/Amex are accepted at ~95% of establishments (hotels, department stores, convenience stores, cafes). [aggregated]
• Carry some cash anyway. Cash is still useful for traditional markets, street food, small/remote operators, and some transit top-ups — keep roughly ₩30,000–50,000 on hand. ATMs marked "Global" accept foreign cards. [aggregated]
• WOWPASS is a popular tourist card combining currency exchange + a prepaid debit card + a T-money transit chip in one. [aggregated]
• Transit/T-money: since March 2026, hundreds of Seoul Metro kiosks accept foreign Visa/Mastercard/JCB/UnionPay/Amex for T-money & Climate Card top-ups, and Apple Pay tap-to-ride is rolling out. [Seoul Metropolitan Government / aggregated]
• Mobile pay: Apple Pay is accepted at major convenience stores, Hyundai department stores and many franchise cafes; Google Pay remains limited for foreign tourists in 2026. [aggregated]
• Diver's note — IMPORTANT. Many dive shops outside Jeju/Busan are small owner-run operations that may prefer cash or Korean bank transfer (계좌이체 / 무통장입금) and may not take foreign cards. Confirm the payment method when you book, and bring cash for shop fees, boat charters and gas/nitrox fills, especially in the East Sea, West Sea and on the islands. [inferred from data/dive-shops pricing/payment notes — verify per shop]

한글 요약: 카드(Visa/Master/Amex)는 대부분 사용 가능하나, 전통시장·노점·소규모 다이브샵은 현금이 필요. ₩3~5만 현금 휴대 권장. WOWPASS(환전+선불카드+T-money)·T-money 교통카드 유용. 제주·부산 외 소규모 다이브샵은 현금/계좌이체만 받을 수 있으니 예약 시 결제수단 확인하고 보트·샵비·나이트록스 충전용 현금 지참.

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7. Language & English-Friendly Shops (언어 장벽·영어 가능 샵 현황) [level: project data — quantified]

This section is quantified from the project's own 81 dive-shop records (data/dive-shops/*.yaml, field foreigner.english_support), not guessed.

Overall (n = 81 shops):

• Of the 44 shops with a documented English level, 26 (≈59%) offer at least basic English. The 37 null records mean "not yet verified," not "no English." [project data]

By region — where the English help actually is:

Takeaways for a foreign diver:

• Jeju (especially Seogwipo) and Busan are the safe choices for English-language service. Independent English sources note that booking East Sea shops can be hard due to limited English handling. [Dive O'Clock — aggregated; project data]
• Elsewhere, book in advance in writing, and rely on a translation app (Papago / Google Translate); have your dive plan, certification level and rental sizes written out in Korean to show the shop.

한글 요약: 자체 81개 샵 데이터 기준 — 영어 유창 9·기초 17·없음 18·미확인 37. 확인된 44곳 중 59%가 최소 기초 영어 가능. 제주(31곳 중 18곳 ≥기초, 유창 9곳 중 7곳)와 부산(유창 2곳)이 외국인 응대가 가장 좋음. 동해(유창 0, 기초 4/33)·울릉도독도·서해는 영어 지원이 약해 사전 서면 예약과 번역앱(파파고) 필수.

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8. Gear, Rental & Nitrox (장비·렌탈·나이트록스)

• Rental gear is widely available; many shops across all regions list equipment rental (full-set rentals roughly ₩50,000–60,000/day seen in East Sea shop pricing). [project data/dive-shops — verified per shop]
• Nitrox / enriched air: 28 of 81 shops in the project data mention nitrox, concentrated in Jeju and the East Sea. Confirm fill availability and your Nitrox certification when booking — do not assume it on remote islands. [project data]
• Exposure protection: the water is colder than tropical Asia. East Sea winter bottom temps can be ~2–4 °C (drysuit advised for deep/winter dives); Jeju ~18 °C in June; Ulleungdo ~21 °C in June. A 5–7 mm wetsuit (or drysuit in winter) is the norm — bring or confirm rental thickness. [region YAML — verified]
• Tank & valve standard (verify): Korean shops use standard aluminum/steel cylinders, but DIN vs yoke (INT) availability and adapter stock vary by shop — verify with the operator if your regulator is DIN-only. [verify needed — no authoritative source in this dataset]
• Flying your own gear in: standard airline checked-baggage rules apply (no compressed-gas cylinders/full tanks in luggage). Confirm dive-gear baggage allowance with your airline. [verify needed]

한글 요약: 장비 렌탈은 전 권역에서 일반적(동해 기준 풀세트 1일 약 56만원). 나이트록스는 81개 샵 중 28곳이 언급(제주·동해 집중) — 인증·충전 가능 여부 예약 시 확인. 수온이 낮아 57mm 웻슈트(겨울/딥은 드라이슈트) 필요(동해 겨울 저층 2~4°C). DIN/요크 밸브·어댑터는 샵마다 달라 사전 확인 필요. 개인 장비 항공 반입은 항공사 수하물 규정 확인.

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9. Why Dive Korea — Selling Points for Foreign Divers (한국 다이빙 셀링포인트)

What to emphasize to international divers (all grounded in the region dataset and independent guides):

1. World-class soft coral at Jeju's Munseom (제주 문섬). Volcanic walls and boulders blanketed in dense, colorful soft coral — compared by dive media to the Maldives / Koh Lipe — plus a rare mix of tropical and temperate species driven by the warm Kuroshio current, all ~5 minutes by boat from Seogwipo. A genuine macro-photography haven, inside a protected Natural Monument. [Dive O'Clock / region YAML — aggregated + verified]
2. Korea's clearest water at Ulleungdo & Dokdo (울릉도·독도). ~20–30 m visibility year-round, up to 40–50 m seasonally, with dramatic volcanic walls, sea caves and large pelagic fish — a remote, far-East-Sea gem few foreigners have dived. [region YAML — verified]
3. Wrecks and offshore shoals in the East Sea (동해). The Gangneung Underwater Park wrecks and the offshore shoal Wangdolcho, with generally good summer visibility and cold-water macro — and it's only 2–3 hours from Seoul, easy to combine with a city trip. [region YAML — verified]
4. Warm island boat diving in the South Sea (남해). Soft coral and seahorses around Geomundo, calm seas and island scenery across two national marine parks, warmer water than the rest of Korea. [region YAML — verified]
5. Four-season variety + uncrowded sites + easy combination with K-culture, food and cities. Korea is well-connected, safe, and still off the international diving radar, so sites are uncrowded. Cultural hook: Jeju's haenyeo (sea women), a UNESCO-recognized free-diving heritage, gives the destination a story beyond the reef. [aggregated]

한글 요약: 외국인 대상 강조 포인트 — (1) 제주 문섬의 세계적 연산호 직벽과 난·온대 어종 혼재(서귀포항 5분, 마크로 천국), (2) 울릉도·독도의 국내 최고 시야(연중 2030m, 시즌 4050m), (3) 동해의 난파선(강릉 해중공원)·외해 암초(왕돌초)와 서울에서 2~3시간 접근성, (4) 남해 거문도의 연산호·해마와 따뜻한 섬 다이빙, (5) 사계절·한산한 포인트·K-컬처/음식/도시 여행 결합, 제주 해녀(UNESCO) 스토리.

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관계 (Relations)

• 권역 / Regions: region-jeju · region-east-sea · region-south-sea · region-west-sea · region-ulleung-dokdo
• 대표 포인트 / Sites: site-jeju-munseom · site-jeju-beomseom · site-jeju-seopseom · site-east-sea-gangneung-underwater-park · site-east-sea-wangdolcho · site-east-sea-ayajin · site-east-sea-yangyang-ingu · site-south-sea-geomundo · site-west-sea-gyeokryeolbiyeoldo · site-west-sea-sibidongpado · site-ulleung-dokdo-dokdo
• 관련 주제 / Topics: topic-certification · topic-monetization

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Sources

• url: https://english.visitkorea.or.kr/svc/contents/contentsView.do?menuSn=177&vcontsId=251923 / publisher: Korea Tourism Organization (VisitKorea) / level: official / accessed: "2026-06-27" / note: K-ETA temporary exemption extended to 31 Dec 2026; K-ETA approval exempts holder from arrival card.
• url: https://www.fragomen.com/insights/south-korea-visit-korea-year-temporarily-exempts-22-countries-from-k-eta.html / publisher: Fragomen, Del Rey, Bernsen & Loewy LLP / level: aggregated / accessed: "2026-06-27" / note: "Visit Korea Year" temporary K-ETA exemption applies to 22 countries/territories.
• url: https://eiglaw.com/south-korea-extends-k%E2%80%91eta-exemption-for-22-countries-through-2026/ / publisher: Erickson Immigration Group / level: aggregated / accessed: "2026-06-27" / note: Full 22-country list (Australia, Austria, Belgium, Canada, Denmark, Finland, France, Germany, Hong Kong, Italy, Japan, Macao, Netherlands, New Zealand, Norway, Poland, Singapore, Spain, Sweden, Taiwan, UK, USA incl. Guam) exempt through Dec 31, 2026.
• url: https://www.mofa.go.kr/ca-en/brd/m_5231/view.do?seq=761797 / publisher: Embassy of the Republic of Korea (MOFA) / level: official / accessed: "2026-06-27" / note: Official MOFA notice — extension of temporary K-ETA exemption until 31 Dec 2026.
• url: https://www.e-arrivalcard.go.kr / publisher: Korea Immigration Service (Ministry of Justice) / level: official / accessed: "2026-06-27" / note: Sole official portal for the mandatory e-Arrival Card (free; file within 72h before arrival). Verify on site.
• url: https://overseas.mofa.go.kr/sg-en/brd/m_2435/view.do?seq=761394 / publisher: Embassy of the Republic of Korea to Singapore (MOFA) / level: official / accessed: "2026-06-27" / note: Jeju visa-free entry — 30-day stay, direct arrival to Jeju only, stay limited to Jeju, ~23 excluded nationalities, K-ETA caveat. (Also cited in region-jeju.yaml)
• url: https://en.wikipedia.org/wiki/Visa_policy_of_South_Korea / publisher: Wikipedia / level: primary / accessed: "2026-06-27" / note: Background on visa-exempt nationalities and Jeju visa-free zone; cross-check only.
• url: https://krsim.net/ / publisher: krsim.net / level: aggregated / accessed: "2026-06-27" / note: Korea eSIM / prepaid SIM / WiFi egg options at airports.
• url: https://esimkr.com/airport-sim-card/icn/ / publisher: esimkr.com / level: aggregated / accessed: "2026-06-27" / note: Incheon Airport SIM counter locations (KT/SKT/LG U+; T1 exits 6–7 & 10–11, T2 exits 4–5) and pre-order pickup.
• url: https://whatsdavedoing.com/buying-sim-card-esim-south-korea/ / publisher: What's Dave Doing / level: aggregated / accessed: "2026-06-27" / note: eSIM-before-departure recommendation; SIM-holder doubles as T-money.
• url: https://ohmyseoul.page/en/guides/korea-card-payment-guide / publisher: Oh my Seoul / level: aggregated / accessed: "2026-06-27" / note: Cards accepted ~95% of places; cash needed for markets/street food; foreign card nuances.
• url: https://english.seoul.go.kr/seoul-implements-open-loop-payments-for-international-tourists/ / publisher: Seoul Metropolitan Government / level: official / accessed: "2026-06-27" / note: Open-loop foreign-card payments for T-money/Climate Card from 2026.
• url: https://korea-insider.com/how-to-pay-korea/ / publisher: Korea Insider / level: aggregated / accessed: "2026-06-27" / note: WOWPASS (exchange + prepaid card + T-money) and Apple/Google Pay status for tourists.
• url: https://www.diveoclock.com/destinations/Asia/South_Korea/Jeju/ / publisher: Dive O'Clock / level: aggregated / accessed: "2026-06-27" / note: Jeju Munseom soft-coral walls (Maldives/Koh Lipe comparison), tropical+coldwater mix, 5-min boat from Seogwipo. (Also cited in region-jeju.yaml)
• url: https://www.diveoclock.com/destinations/Asia/South_Korea/Sokcho/ / publisher: Dive O'Clock / level: aggregated / accessed: "2026-06-27" / note: East Sea most popular among locals but hard for foreigners to book (limited English). (Also cited in region-east-sea.yaml)
• url: https://www.padi.com/diving-in/south-korea/ / publisher: PADI / level: aggregated / accessed: "2026-06-27" / note: General Korea dive-destination overview / selling points.
• Project data (level: primary, internal): /Users/jikwangkim/work/divetokorea/knowledge-base/data/regions/.yaml (region-jeju, region-east-sea, region-south-sea, region-west-sea, region-ulleung-dokdo) — access.gateways/from_seoul/from_abroad, characteristics; and /Users/jikwangkim/work/divetokorea/knowledge-base/data/dive-shops/.yaml (81 records) — foreigner.english_support distribution, nitrox/rental/pricing. accessed: "2026-06-27".

Verify-needed items (불확실 — 추가 확인 필요)

• K-ETA exact eligible-country list, fee, and validity — confirm on k-eta.go.kr per nationality (changes periodically).
• Jeju visa-free excluded-nationality list (~23) — exact list shifts; confirm on official MOFA / Jeju immigration notice.
• e-Arrival Card edge cases (who is exempt beyond valid-K-ETA holders) — confirm on e-arrivalcard.go.kr.
• Tank valve standard (DIN vs yoke) and adapter availability by shop — no authoritative dataset source; confirm with each operator.
• Per-shop payment methods (foreign card vs cash/계좌이체) and nitrox fill availability outside Jeju — verify per shop at booking.
• Ulleung Airport opening — currently ferry-only; update access when the airport opens.
• English-support null shops (37/81, 46%) — unverified, not confirmed "no English"; field needs follow-up research.