Susami Underwater Postbox
Send a postcard from the world's deepest underwater postbox in Susami Bay, Japan. A unique dive experience with vibrant marine life.
Highlights
Must-see attractions
Social
From TikTok & Reddit
Best Time
Pleasant water temperatures
Susami Underwater Postbox
Best Time
Pleasant water temperatures
Highlights
Must-see attractions
Send a postcard from the world's deepest underwater postbox in Susami Bay, Japan. A unique dive experience with vibrant marine life.
"It was both surreal and awesome to see a mail box just sitting on the flat bottom of the ocean."
waterproof postcards
Bring your own waterproof postcards and pens, or purchase them from local dive shops.
Book a Guided Dive
A guided dive ensures safety and helps you spot the best marine life and the postbox.
Quick Facts
Hours
Rating
4 · 21 reviews
Type
Tourist Attraction
Highlights
Discover the most iconic attractions and experiences
The Deep Sea Postbox
Susami Bay, 10 meters underwater
Send a postcard from the world's deepest functioning underwater mailbox, a truly unique and memorable experience.
Vibrant Coral Reefs
Near the postbox
Discover a thriving hard coral reef teeming with colorful fish, including clownfish and other fascinating marine species.
Marine Encounters
Susami Bay waters
Keep an eye out for sea turtles and a variety of other captivating sea creatures during your underwater exploration.
Plans like a pro.
Thinks like you
Planning Your Visit
Dive In for a Unique Mail Experience
Beyond the Mailbox: Explore Marine Life
Best Times
Insider Tips
from TikTok, Instagram & Reddit
waterproof postcards
Bring your own waterproof postcards and pens, or purchase them from local dive shops.
Book a Guided Dive
A guided dive ensures safety and helps you spot the best marine life and the postbox.
Check Mailbox Maintenance
The postbox is regularly maintained; old ones are displayed at Club Noah Susami.
Capture the Moment
Consider renting an underwater camera to document your unique mailing experience.
Tips
from all over the internet
waterproof postcards
Bring your own waterproof postcards and pens, or purchase them from local dive shops.
Book a Guided Dive
A guided dive ensures safety and helps you spot the best marine life and the postbox.
Check Mailbox Maintenance
The postbox is regularly maintained; old ones are displayed at Club Noah Susami.
Capture the Moment
Consider renting an underwater camera to document your unique mailing experience.
Postcard Delivery
Postcards sent from the underwater box will actually arrive at their destination.
What Travellers Say
Reviews Summary
Visitors rave about the surreal and awesome experience of diving to the underwater postbox, calling it a unique tourism gimmick that delivers. Beyond the mailbox, the vibrant coral reefs and abundant marine life, including clownfish and sea turtles, are a major highlight. Guides are praised for their knowledge and friendliness, making the dives smooth and safe.
"I did my first scuba dive since the onset of COVID here in September of 2023. What a great experience!
It was both surreal and awesome to see a mail box just sitting on the flat bottom of the ocean. It wasn't just a tourism gimmick though. There's plenty of things to see and enjoy at this location. The hard coral reef near here is awesome! We saw several pairs of clown fish that came out to challenge us when we got close to their anemones, a whole range of other very colorful fish, and I was lucky enough to spy a sea turtle even though it was too far away to capture it on camera.
Our guide Shiomi was also friendly, knowledgeable, and made sure that our dive went smoothly and safely. The cost of the dive was also VERY reasonable at around ¥16,000 for full equipment rental, the guide fee, and underwater camera rental. I look forward to diving with Club Noah again."
Bryan Baier
"I love the heartwarming seasonal plans the staff puts together."
MAKOTO MOROKOSHI (ココモ)
"After exploring the ocean floor with an instructor at Club Noah Susami, you can actually drop off a letter in the mailbox. The mailboxes are regularly maintained and replaced with new ones, and you can see the old mailboxes at Club Noah Susami."
Tatsuhito Masuyama
What People Like
What People Dislike
Frequently Asked Questions
🚇 🗺️ Getting There
The Susami underwater postbox is located in Susami Bay, Wakayama Prefecture, Japan. Access is primarily through scuba diving or snorkeling tours. You'll likely need to travel to Susami Town and then arrange a boat trip with a local dive operator like Club Noah Susami.
The postbox is situated 10 meters underwater, making scuba diving or advanced snorkeling the primary methods of access. Some boat tours might offer views from above, but direct interaction requires being in the water. 
The nearest major transport hubs are likely Osaka or Wakayama City. From there, you can take a train to Susami Station, followed by a taxi or local bus to the dive centers.
Yes, many dive shops in Susami Bay offer boat tours that take you to the postbox location. These tours often include opportunities for snorkeling or diving.
Travel times can vary significantly depending on your starting point in Japan. From Osaka, it can take several hours by train. It's advisable to plan your journey in advance.
🎫 🎫 Tickets & Entry
There isn't a direct 'ticket' for the postbox itself. However, you will need to book a scuba diving or snorkeling tour, which includes access to the postbox site. Prices vary by operator.
A guided dive with equipment rental and access to the postbox can cost around ¥16,000, as reported by a visitor. Prices may vary.
For scuba diving, you'll typically need a certification. Beginners might be able to do a 'discover scuba diving' experience with an instructor. Snorkeling has fewer restrictions.
Dive tour operators usually run trips throughout the day, weather permitting. It's best to check with your chosen operator for their specific schedule.
Yes, many dive shops and tour operators in Susami Bay offer waterproof postcards and pens for purchase, often for around 180 yen each.
🎫 🤿 Onsite Experience
The world's deepest underwater postbox is located 10 meters (approximately 33 feet) below the surface of Susami Bay.
Visitors often report seeing vibrant coral reefs, various colorful fish like clownfish, and sometimes even sea turtles.
The postbox is regularly maintained and old ones are displayed at Club Noah Susami.
Yes, postcards mailed from the underwater postbox are collected and will be delivered to their intended recipients.
Absolutely! The area boasts an impressive hard coral reef with abundant marine life, making it a great spot for exploration beyond just mailing a letter.
📸 📸 Photography
Using a waterproof camera or a waterproof phone case is essential. Renting an underwater camera is also an option offered by some dive centers.
The vibrant coral reefs and diverse marine life offer excellent photographic subjects. Capturing clownfish near anemones or a sea turtle can make for stunning shots.
Natural light diminishes significantly at 10 meters. Consider using an underwater strobe or video light for better color and detail in your photos.
Yes, you can take photos of the bay and the surrounding coastline from the boat before or after your dive.
Generally, there are no specific restrictions on photography underwater, but always be mindful of other divers and marine life.
Social
from TikTok, Instagram & Reddit