Atami Kosoga Cave
★★★★☆
(209)
Kosoga Cave in Atami, Shizuoka, is open Nov–Apr and features a 40m semi-enclosed cave at 6–12m depth, ideal for beginners. Its wide space and open ceiling let sunlight create a stunning blue gradation. Just 10 minutes by boat from Atami Port, it’s both scenic and accessible.
The cave hosts schools of snappers, rockfish, and mackerel flowing like a river under light, with nearby sands hiding sharks and bullhead sharks.
Dive Activity & Environmental Conditions
Top Wildlife Sightings
Most frequently spotted marine life based on dive logs
#1
Moray Eel
12
Total Sightings
J
F
M
A
M
J
J
A
S
O
N
D
#2
Damselfish
11
Total Sightings
J
F
M
A
M
J
J
A
S
O
N
D
#3
Pufferfish
9
Total Sightings
J
F
M
A
M
J
J
A
S
O
N
D
#4
Boxfish
7
Total Sightings
J
F
M
A
M
J
J
A
S
O
N
D
#5
Wrasse
5
Total Sightings
J
F
M
A
M
J
J
A
S
O
N
D
#6
Grouper/Basslets
4
Total Sightings
J
F
M
A
M
J
J
A
S
O
N
D
#7
Jackfish
4
Total Sightings
J
F
M
A
M
J
J
A
S
O
N
D
#8
Scorpionfish
4
Total Sightings
J
F
M
A
M
J
J
A
S
O
N
D
#9
Surgeonfish
4
Total Sightings
J
F
M
A
M
J
J
A
S
O
N
D
#10
Nudibranch
4
Total Sightings
J
F
M
A
M
J
J
A
S
O
N
D
