Izu Peninsula diving: my top 5 dive sites

This post may contain affiliate links. It means I may earn a commission if you book or purchase something. This is at no cost to you and support this website. Learn more here.


From the very first time I went diving in Japan in February 2017 to my last trip in October 2019, the Izu Peninsula quickly became my happy place on mainland Japan. Peaceful while being at a reasonable distance from lively Tokyo, I visited the area 8 times in all seasons including 6 scuba diving trips with my dive club in Tokyo.

The Izu Peninsula is the easternmost area of the Shizuoka Prefecture, the closest to Tokyo (Atami is a 45-minute ride away with the Shinkansen bullet train). Right down the south slopes of Mount Fuji, they form together with the Fuji-Hakone-Izu National Park. In addition to the world-famous Japanese volcano, its breath-taking natural landscapes feature many geological wonders and the best shore diving in mainland Japan. After scuba diving at 7 different locations of the Izu Peninsula, here are my top 5 sites of Izu Peninsula diving.

1 – Osezaki

Osezaki - diving Izu Peninsula - Japan

Osezaki was by far one of my favourite dive sites in mainland Japan, taking the 1st place to Izu Ocean Park, which used to be my number 1. Although being more remote on the west coast of the Izu Peninsula, the incredible soft coral and macro marine biodiversity, a shore diving within the grounds of a Shinto Shrine, and incredible views of Mount Fuji were the reason why Osezaki made it to my top 10 dives of 2018.

My favourite dive in Osezaki was Sentan. Due to strong tidal currents, it is only accessible once a day at slack tides. After paying to enter the shrine grounds, your scuba diving gear on a trolley, watch out for the water entry. It is not easy as you need to walk fully equipped on big round pebbles. Once underwater, there is a gentle slope made of large boulders and bright pink soft coral. The amount of marine life was just stunning: fire sea urchins, sea anemones, boxfish and many nudibranchs.

I hope I will have the opportunity to return one day to hopefully find this time the “Pikachu” nudibranch or sunfish which are frequently seen.

To reach Osezaki, it is preferable to rent a car (be careful you might need a special translation of your driving licence like me), but a determined dive traveller can take the train to Numazu Station and continue by bus (about 5 hours from Tokyo). But once arrived at Osper Dive House, you will forget the long ride thanks to the fantastic hospitality of Nishibori san and his wife. In addition to tanks and gear, they offer accommodation and delicious home-made meals.

Maximum depths from 15 to 60 m

2 – IOP (Izu Ocean Park / Izu Kaiyo Koen)

Diving Izu Peninsula - IOP Japan

The Izu Ocean Park is south of the Jogazaki Coast, a famous walking trail of the Izu Peninsula. It is by far the most popular shore dive site of the area. Due to the waves, the entry from the beach can sometimes be sporty, so hold the rope tight.

There is first a shallow part where you can find many sea anemones and damselfish. Then by following the line, there are two possible itineraries: the IOP underwater post box or the wall. The latter is, of course, my favourite part as it is going deeper and deeper until a sandy bottom at 40 m. Featuring beautiful pink and purple soft corals, there is always a lot of fish action at IOP wall with stingrays, flounders, bumphead wrasse, butterflyfish and dragon moray eels.

Maximum depths from 10 to 40 m

3 – Atagawa

Diving Atagawa Izu Peninsula Japan

After hearing so much about it, I finally went diving twice in Atagawa at the end of 2018. Its location is just a bit further south of IOP on the east coast of the Izu Peninsula. Its name means “Hot River”, and there is an actual hot spring river flowing across the town into the sea!

The dive site of Atagawa is an interesting mix of rocky reefs, soft corals and sand patches with a rich marine fauna including lionfish, anemone fish, flying gunards and nudibranchs. Thumbs up to the incredible hospitality of Kazu san at the PONO Cafe, for plenty of Aloha spirit in Japan!

Maximum depths from 10 to 40 m

4 – Atami

Diving Izu Peninsula - Atami Japan

From Atami harbour, with only a 5-minute boat ride, you can dive on the only shipwreck of the Izu Peninsula east coast. If you love soft corals, you have to know the shipwreck in Atami is entirely covered in them and come in yellow, purple, pink and orange. There are many exciting features to check on this superb wreck dive with the bow and its winch, the hull and especially the part which broke allowing you to see inside with a quality diving torchlight.

Maximum depths from 20 to 40 m.

5 – Koganezaki

Diving Izu Peninsula - Koganezaki Japan

Located on the west coast of the Izu Peninsula, Koganezaki beach park offers a campsite and a dive centre to go shore diving. You can also go diving by boat from the harbour of Arari to reach deeper dive sites. It is just a short car ride away.

The surroundings are stunning, but unfortunately, due to the poor visibility at the time of my visit, I don’t think I could appreciate the site at its most. On the first day, I did 2 beach dives, and I saw only one nudibranch, whereas it was supposed to be the best place for macro photography in the Izu Peninsula. On the second day, I went on 2 boat dives around the same 2 pinnacles covered in soft coral, I saw much more fish, but again the visibility was so reduced that I don’t understand how the other buddy team saw those eagle rays!

To reach Koganezaki, it is preferable to rent a car (be careful you might need a special translation of your driving licence like me), but a determined dive traveller can take the train to Shuzenji Station and continue by bus (about 4 hours from Tokyo).

Maximum depths from 15 to 30 m

Other dive sites of the Izu Peninsula

Diving Izu Peninsula - Toi Shipwreck Japan


Toi is a small harbour on the west coast of the Izu Peninsula and offers small wreck dive sites. While the main shipwreck itself is not that impressive, it made a decent deep dive at 30m with clear visibility and plenty of opportunity for my dive buddy and I to play with our camera. We paid for a boat dive, but it was actually possible to do it as a shore dive (which would have been much cheaper).

Maximum depths from 15 to 30 m


Only 25 minutes of ferry from Atami, the north shore of the small island offers a rocky dive site in its shallowest part with many eels and nudibranchs hiding between the boulders. On my first dive, I saw a big sea hare of about 30 cm. As you swim further away, some cage structures were installed to create artificial reefs where you can see many other fish species and soft corals. On my way back, I saw a guitar shark and many dragon moray eels. For information, the visibility was pretty low the day I went diving there, and despite being usually good at navigation, I got lost twice, so bringing a compass is definitely a good idea.

Maximum depths from 10 to 25 m

When is the best season to go scuba diving in the Izu Peninsula?

Diving Izu Peninsula - Osezaki Japan

The Izu Peninsula shore dive sites are accessible all year long. However, during the typhoon season, sites can be sometimes closed for safety reason (usually July and September).

In summer (July- September), water temperatures are about 24°C. A 5 mm wetsuit will be a comfortable choice.

During the wintertime (December-April), the minimum temperature is 15°C. It is not so warm, but still diveable in a 7mm wetsuit at the same time. I personally prefer using my drysuit now whenever water temperatures are below 18°C.

How to go from Tokyo to the Izu Peninsula?

Jogazaki Kaigan train station

You can reach some of the most beautiful dive sites of mainland Japan from Tokyo on a day trip by only using trains: Atami, Izu Ocean Park, and Atagawa.

From Tokyo Central Station take a train ticket to Atami. There are two options: the fastest is by using the bullet train (Shinkansen), it is more expensive, but it only takes 45 min. The local JR Tōkaido line also goes all the way to Atami, but the train stops at almost every station. It is much cheaper, but it takes about 2 hours.

To continue to IOP and Atagawa, you need to change trains in Atami to the local JR Itō line. With a bit of luck, you will ride in one of the panoramic trains, and one of them has a fish theme decoration. For IOP, stop at Jogasaki-Kaigan Station, you can walk there in 20 minutes but if you take all your scuba diving gear with you might prefer to take a taxi (at least on the way back due to the slop between the train station and the dive centre).

Where to stay in the Izu Peninsula?

K's House Ito guesthouse Izu Peninsula

Ito – K’s House

I promise I’m not exaggerating, but this is my favourite accommodation in mainland Japan. I tried it a first time in December 2018 during a weekend with a friend to see the autumn leaves (Momiji). I went back in October 2019 to relax before resuming my underwater adventures in Okinawa.

K’s House in Ito is a historical heritage century-old “ryokan” (traditional Japanese inn). The small Japanese chain of hostels turned it into a fabulous guesthouse. They offer both private rooms and a dormitory (female only available). I tested both. By sharing with friends, the private room is affordable. If you choose the dormitory, you can still enjoy the ryokan experience by sleeping in a futon on a tatami floor after a relaxing bath at their private onsen (hot spring) facility. The shared living room is so lovely with its terrace along the river that I managed to spend there an entire day reading, writing and cooking in the guest kitchen.

Note there is not much to do and see in Ito, but there are plenty of little “izayakas” (pubs) with mouth-watering food at reasonable prices. Ito is also ideally located in the middle of Atami, Jogazaki-Kaigan and Shuzenji. Thanks to the bus network starting from Ito, with day passes at only 1300 ¥ (about 11€), it’s the perfect base to explore the Izu Peninsula and go scuba diving.

Do you want to learn more about travelling and scuba diving in Tokyo area and the Izu Peninsula, have a look at these other articles:

If you enjoyed this post, subscribe to WAD Newsletter to receive the latest posts directly into your inbox.


Posted by Florine

Leave a Reply