Yonaguni Diving — Japan

Yonaguni is Japan's westernmost island, famous for two things: schools of 100+ hammerhead sharks from November to March, and the mysterious underwater 'monument' — terraced stone structures at 25m that may be natural or man-made. The hammerhead season coincides with excellent 30m+ visibility and dramatic underwater scenery.

Score
66.7 / 100
Country
Japan
Region
Asia-Pacific
Area
Okinawa Prefecture
Nearest airport
Yonaguni (OGN)
Visibility
15–49 m
Water temperature
21–29 °C
Max depth
40 m
Current strength
moderate
Dive types
reef, pelagic
Best months
December, January, February, March, April, May
Minimum certification
Open Water
Access type
boat
Average 2-tank dive cost
$100 USD
Budget tier
mid range
Key species
manta ray, whale shark, reef shark, sea turtle, seahorse, nudibranch, cuttlefish, whale
Google rating
0 (0 reviews)
Top operators
Yonaguni Diving Service, Sou Wes Dive
Nearest hyperbaric chamber
University of the Ryukyus Hospital Chamber, Naha (~120 km)
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World Class
Intermediate
Yonaguni
JapanAsia-Pacific
66.7

SCORE

24.4500°N

122.9500°E

Yonaguni is Japan's westernmost island, famous for two things: schools of 100+ hammerhead sharks from November to March, and the mysterious underwater 'monument' — terraced stone structures at 25m that may be natural or man-made. The hammerhead season coincides with excellent 30m+ visibility and dramatic underwater scenery.

Japan's Mysterious Underwater Monument

Visibility15–49 m
Temperature21–29°C
Max Depth40 m
Currentmoderate
2-Tank Dive$100
Best MonthsDecember, January, February, March
CertificationOpen WaterIntermediate

Score Breakdown

Click any score to see a detailed breakdown

ML80.0CH72.0VIS80.0SV39.0TMP59.0DA62.0OP78.0TS64.0GT68.0VAL54.0CRD57.0SP57.0

Marine Life

80.0

Species diversity, megafauna encounters, reef fish abundance, macro life, and endemic species.

Species Diversity
100
Megafauna Encounters
56
Reef Fish Abundance
100
Macro Life
60
Endemic Species
70
Marine Life Diversity
80.0
Coral & Reef Health
72.0
Visibility & Conditions
80.0
Dive Site Variety
39.0
Water Temperature
59.0
Depth & Access
62.0
Operator Quality
78.0
Topside Experience
64.0
Getting There
68.0
Value & Cost
54.0
Crowding
57.0
Social Proof
57.0

Key Species

manta raywhale sharkreef sharksea turtleseahorsenudibranchcuttlefishwhale

Dive Types

reefpelagic

Traveling with Non-Divers?

Your non-diving travel companions will find plenty to enjoy topside while you're underwater. Here are some activities to consider.

Activities for Non-Divers

Yonaguni horse ridingDr. Ishi monument (westernmost point of Japan)Tindahanata cliff viewpointlocal awamori distillery tour

Nearby Cultural Sites

  • Yonaguni Submarine Ruins (viewed from glass-bottom boat)
  • Kubura Bari rock formations

Non-Diver Partner Score

4/10

Limited topside — plan ahead for non-diving partners.

Family FriendlyYes
Restaurants & Nightlifebasic

Safety & Emergency

Dive Insurance

Dive insurance is essential. Standard travel insurance often excludes scuba diving. We recommend DAN (Divers Alert Network) for comprehensive dive accident coverage.

Learn More at DAN.org
Hyperbaric Chamber120 km — University of the Ryukyus Hospital Chamber, Naha
Nearest Hospital3 km

Small clinic on island; flight to Naha (1.5 hrs) for chamber; helicopter available

Skill LevelIntermediate
Current Strengthmoderate

Top Operators

Yonaguni Diving Service

PADI

4.7
120 reviewsNITROX

Sou Wes Dive

PADI

4.6
90 reviewsNITROX
Compare This Dive Site
Current conditions
9/10
Waves1.54 m
Swell1.4 m
Wind14.1 km/h
Air25.9°C
Mainly clear
9d ago
Honest reality check

What your dive shop won't tell you

The minimum certification printed on a brochure is the legal floor, not the honest recommendation. Here's what we actually think you should bring to this site.

Recommended logged dives
40+

Below this we'd send you somewhere easier first.

Recommended certification
Advanced Open Water
“Intermediate minimum — deep profiles and variable viz.”

What will challenge you

  • →Moderate currents. Expect to drift — this is not a skill-builder site for a first trip after certification.
  • →Recreational limit of 40 m is reachable here (max depth 40 m). Gas planning and NDL tracking matter.
  • →Cooler than most tropical sites — 21°C minimum. A 5 mm wetsuit is the floor for longer dives.
  • →Variable visibility
  • →Deep profiles

What will surprise you

  • →Thermoclines can drop water temp by 8°C between the surface and depth. Your wetsuit choice should match the minimum, not the average.
  • →Yonaguni has more marine life variety than most divers expect
  • →Local operators know spots the guidebooks miss
Time of day

When to dive it

Every dive shop gives you this briefing at 7am. We just wrote it down. Tidal dependency: slight. Optimal window: First light to 11am for best visibility..

Morning
  • Viz
    peak
  • Current
    moderate
  • Crowd
    light
  • reef exploration
  • photography

Best light and calmest conditions before afternoon wind picks up.

Afternoon
  • Viz
    moderate
  • Current
    moderate
  • Crowd
    moderate
  • drift diving
  • second tank

Wind chop can reduce viz. Still diveable but morning is better.

Month-by-month

Dive forecast

Realistic conditions by month. Viz ranges are what you should actually expect, not best-case marketing numbers. Confidence % is the share of days that match this profile historically.

Month Viz (m) Temp (°C) CurrentSea RainConfidenceHighlights
Jan32–4925ModCalmLight70%reef fish active, peak season crowds
Feb32–4925ModCalmLight70%reef fish active, peak season crowds
Mar32–4925ModCalmLight70%reef fish active, peak season crowds
Apr32–4925ModCalmLight70%reef fish active
May32–4925ModCalmLight70%reef fish active
Jun15–3227ModModWet70%reef fish active
Jul15–3227ModModWet70%reef fish active, manta season
Aug15–3227ModModWet70%reef fish active, manta season
Sep15–3227ModModWet70%reef fish active, manta season
Oct15–3227ModModWet70%reef fish active
Nov32–4925ModCalmLight70%reef fish active
Dec32–4925ModCalmLight70%reef fish active
Shoot here

Photography brief

Subjects are only half the shot. A perfect macro site is useless in a three-knot drift, and a wide-angle dream is useless at 35 m with a murky ceiling. These are the conditions, not the hype.

Macro subjects66
Wide angle67
Viz stability23
Hover friendliness70
Natural light56

Recommended kit

  • →General reef kit — mid-range wide or a 60mm macro depending on the specific site
Level up here

What this site will teach you

The dives that made you a better diver are the ones that made you uncomfortable for the right reasons. Here's what this site will quietly train you for.

What it costsEstimates — calibration pending

7-day trip, per person

Rough ranges anchored to existing regional data — not booking quotes. Land-based trip, standard breakdown.

Budget
$2,200–$3,050

Hostels, shore diving, cheap eats

Flights (RT from US)
$1,100–$1,300
Accommodation / day
$50–$100
Diving / day
$90–$100
Food / day
$10–$25
Transfers + misc
$50–$150
Mid-range
$3,350–$4,850

3-star hotels, standard boat ops, mix of restaurants

Flights (RT from US)
$1,550–$1,850
Accommodation / day
$120–$220
Diving / day
$100–$130
Food / day
$30–$60
Transfers + misc
$50–$150
Splurge
$5,500–$8,550

Top resorts or liveaboards, premium operators

Flights (RT from US)
$2,250–$2,750
Accommodation / day
$260–$500
Diving / day
$130–$170
Food / day
$70–$140
Transfers + misc
$50–$150

Flights priced round-trip from a major US hub. Figures are per person on a shared room. Solo travelers add ~30% to accommodation.

Pair with

Build a trip around it

Most divers fly across the world for one destination and don't realise another worth-it site is 90 minutes away. Here are the honest pairings.

Best dive types here