Susami is a small fishing town in Wakayama Prefecture, Japan, with a population of around 3,700 people. By 1999, it was the kind of place tourists drove through without stopping. Toshihiko Matsumoto, the town’s 70-year-old postmaster, thought he could fix that. His solution was to sink a working mailbox into Susami Bay, 10 meters below the surface. “I thought it would be interesting if divers could send letters from under the sea,” Matsumoto, who worked for the post office for about 40 years, said in a video by Great Big Story. “I thought it would be good for the post office and good for tourism.” How to sink a letter The logistics were considerable. Standard postcards dissolve underwater, so Matsumoto arranged for waterproof plastic postcards to be sold at the local dive shop, along with oil-based markers that wouldn’t smear. The bright red cast iron mailbox was anchored to the ocean floor and connected to Susami’s official post office, making it a fully functioning branch of the Japanese postal system. Because the boxes rust underwater, they are replaced every six months—two boxes alternate, with the rusty one repainted and waiting while the other is in service. The process for sending a letter is straightforward, if unconventional. Visitors buy a waterproof postcard for around $1.50 at Club Noah Susami, the local dive shop. Then, they write their message with the provided markers, and dive down to deposit it in the box. For beginners, guided beach diving lessons are available. Every day, the shop’s manager dives down to collect whatever has accumulated and delivers it to the local post office where the letters go out to recipients anywhere in the world. A scuba diver rises to the surface. Photo credit: allianoi via Canva. Some unexpected fame The underwater post box earned a Guinness World Record for the deepest underwater post box in 2002. The mailbox receives around 1,000 to 1,500 pieces of mail each day. By the time Great Big Story posted their video (which has since passed a million views) more than 38,000 letters had been successfully delivered from the ocean floor. The box even appeared in a Daihatsu automobile commercial in 2015. Matsumoto’s instinct turned out to be correct. Susami, which had nothing particular to recommend it to outsiders, now draws divers from around the world to mail a letter from the bottom of the bay. It is, by any measure, one of the more creative acts of small-town economic revival on record, conceived by a 70-year-old postmaster who just thought it would be interesting. “I thought it would be good for the post office,” he said, “and good for tourism.” Looks like he was right on both counts. The post A struggling beach town needed tourists, so its postmaster sank a mailbox 30 feet underwater appeared first on Upworthy.