Also known as Dunan (どぅなん) in the local language, Yonaguni is a tiny speck of an island (28 sq. km.) with a population of less than 2000, located 125 km from Taiwan and 127 km from Ishigaki. The main population centers are Sonai (祖内) on the north coast, Kubura (久部良) on the west coast and tiny Higawa (比川) in the south. The total population is about 1700.
Although it lacks the resorts of the larger Yaeyama islands and its few visitors are mostly divers coming to witness the island's mysterious sunken ruins and hammerhead sharks, the island has beautiful (yet uncrowded) beaches, cultural attractions, and various mysteries of history.
Yonaguni is notorious for its local language, brewed in isolation for centuries, which even those from mainland Okinawa find utterly incomprehensible. Pronunciation can be a bit easier than that of neighboring Miyako islands, though, as the central vowels and word-final consonants are absent here. Language buffs can pick up Nae Ikema's Yonaguni-go Jiten (与那国語辞典) at the airport shop.
The only words the casual visitor is likely to run into though are waːriː (ワーリー) and fugarassa (フガラッサ), Yonaguni for "welcome" and "thank you", respectively, as standard Japanese is spoken by practically everybody (the locals are bilingual), and Chinese is understood by some.
The Wild, Wild West
After the end of World War II, Yonaguni's tiny fishing port of Kubura became a hub of black marketeers shipping goods (mostly stolen) from Japan to Taiwan in exchange for food and other scarce commodities. At the boom's peak the island's population had swelled to 20,000, including 38 bars and 200 hostesses. Alas, with the post-war normalization of economic conditions the black market vanished and Yonaguni returned to its quiet ways.
Yonaguni is among the remotest inhabited spots of Japan and getting there is both inconvenient and expensive, although this may change if connections to Taiwan improve. Both flights and ferries may be cancelled at short notice if the weather is bad (particularly around typhoon season), so allow some buffer in your plans.
Expanded in 1999 to allow jets to land, tiny Yonaguni Airport (OGN) fields 1-2 flights daily from Ishigaki on Japan Transocean Air and Ryukyu Air Commuter (30 minutes, ¥10000/17000 one-way/return), and RAC flights 3 times a week from Naha.
In addition, TransAsia Airways  operates irregular charter flights from Hualien, Taiwan (40 min, around ¥5000 one-way). Check with the airline or call 0980-87-2241 in Yonaguni for more information.
Fukuyama Kaiun (福山海運), tel. 0980-87-2555, runs boats from Ishigaki on Wednesdays and Saturdays, with return trips on Mondays and Thursdays, always departing at 10 AM. The trip takes four hours on a good day and costs ¥3460/6580 one-way/return; note that most of the journey is across the open sea and people prone to seasickness may wish to steer clear. A cargo boat also offers an irregular (unscheduled) service to Naha.
Star Cruises  operates irregular cruises in the summer season only from Keelung (Taiwan) to Yonaguni. As of 2009, they're running again after a pause of a few years.
There are 7 buses per day between Sonai and Kubura, 3 of which continue on to make a full circuit of the island of the west half of the island, but there is no public transport on the eastern side. Somewhat incredibly, all buses are free.
2 taxis are also available, and a circuit of the island by car takes about an hour. There are at least 4 or 5 different rent-a-car places, including SSK  right in front of the airport (from ¥5000 for a full day), and motorbikes and bicycles are also readily available.
More or less all diving shops and lodgings offer free transfers to and from the airport if you book ahead.
Capes, cliffs and beaches
Marker for the westernmost point in Japan, Cape Irizaki
Cape Irizaki (西崎). Yonaguni's main aboveground sight of any interest is the marker for the westernmost point of Japan (日本最西端の碑), located here at the westernmost tip of the island, about a kilometer from Kubura (15 minutes on foot).
Cape Agarizaki (東崎), at the east tip of the island. The kanji mean East Cape, but the reading of the name refers to the rising sun. You can observe it from a cliff. On a clear day, if you're lucky, you can see the coast of Iriomote. Also a grazing area, many Yonaguni horses can be found here.
Kuburabari (久部良バリ). This cliff near the northern side of Kubura's port offers views of the last sunset in Japan, and on a good day it is possible to see the shadow cast by Taiwan in front of the setting sun from here. This is also the site where, in the rough period when residents of the island were forced to pay an alarmingly expensive head tax after the Ryukyu Kingdom was conquered by the Satsuma clan from the Japanese mainland, pregnant women were sometimes made to jump to their death to avoid an increase in population.
Ubudumaihama (ウブドゥマイ浜). From the cliffs here, there's an impressive view of much of Yonaguni's beautiful northern coastline.
Hikawa Beach (比川浜 Hikawahama). Located on the southern shore of the island in Hikawa. Shaped like a crescent, it is the island's largest beach. Suitable for swimming. Very quiet, little to no waves because of a coral reef.
Kuburadake (久部良岳). Kuburadake is a Natural Conservation District in the west of Yonaguni, about 188m above sealevel. It is valuable because it contains both a Chinquapin mountain forest and a lowlands forest, home to such natural monuments as the colorful Emerald Dove (リュウキュウキンバト), Japanese Wood Pidgeon (ヨナグニカラスバト), Ryukyu Robin (ウスアカヒゲ), and others. From about halfway up the mountain to the summit, the trees are mostly date palms. Lower than halfway, you can find Javanese bishopwood trees (アカギ) and other diverse plants which the Atlas moth eats.
Tindabana (ティンダバナ). Tindabana is a natural rock formation with a nice view. About 70m tall. From Tindabana, you can see the entire village of Sonai, and Nandahama. According to tradition, the great empress of Yonaguni, Sanai Isoba, resided here.
The following rock formations are best viewed by boat.
Gunkan-iwa (軍艦岩). The "Battleship Rock", about 2km south of Agarizaki, is a series of peculiarly-shaped reef rock formations. Supposedly, the main rock bears a close resemblance to the shape of a battleship, and that's how it got it's name. It can be observed from Sanninudai.
Sanninudai (サンニヌ台). Believed by some to be an above-water portion of the mysterious undersea ruins because it is shaped almost like a sort of stairway. The strangely-shaped rocks of Gunkaniwa can be easily seen from here. Also, there's a rock here with some writing on it which is mysterious. It bears little resemblance to kaida-dii, the island's indigenous writing system, and some have even suggested that it is Phoenecian.
Tatigamiiwa (立神岩、タティガミイワ). The "Standing God Rock", at the southeast tip of the island, is also noted for the underwater ruins nearby (see Do, some with what appears to be indigenous writing. Also, it's considered a spiritual site for followers of Yonaguni's indigenous traditional religion.
Tunguta (トゥングタ). Tunguta is a rice field in the middle of the island, of historical interest. In the period when a head tax was enforced by the Shimazu clan of modern-day Kagoshima prefecture against the people of the southern islands, causing much pain and suffering, all the inhabitants of the island were suddenly called to this ricefield. Those who did not get there by a certain time were slaughtered. This was one of a few horrific stories of population reduction which was carried out on Yonaguni by the order of the local elders.
Yonaguni Ethnographic Museum (与那国民族資料館 Yonaguni Minzoku Shiryōkan, literally "Yonaguni Ethnicity Information-center"). This museum, at No. 49 in the Sonai area, is run by 87-year-old "island auntie", Ikema Nae. There's a lot of information about the island's history, culture, and even language. If you want information about the island's indigenous writing system, kaida-dii, this is probably the place to go. Their informational pamphlets can also be very enlightening, but they are only occasionally offered in English. The museum also sells the Dictionary of the Yonaguni Tongue (与那国語辞典 Yonaguni kotoba jiten), the only available dictionary of the local language (to and from Standard Japanese), also with a little bit of information about the native writing system. Incidentally, the dictionary is written by Ms Nae, and the entire museum is mostly the result of her work. If you have any questions, she's usually there and is very knowledgable about the history, culture, language, and traditions of Yonaguni.
The island's unique fauna are also of interest.
Yonaguni horse (ヨナグニウマ yonaguni-uma). Bred in isolation on Yonaguni over hundreds of years, the Yonaguni horse is a very small breed, only about 10 hands high (100 centimeters/3.5 feet). Nowadays, most are wild, in two free-ranging herds (about 108 horses total). They're generally very tame and gentle, thanks in large part to the kind treatment they receive from the islanders. You'll probably see at least one if you're on the island for very long.
Atlas moth (ヨナグニサン yonaguni-san). The largest known species of moth in the world. Although it can be found in other parts of Asia (mostly in Taiwan, India, and Malaysia), the first specimen was collected in Yonaguni and they are abundant. The Atlas Moth Museum (アヤミハビル館 ayamihabiru-kan) southeast of Sonai (tel 0980-87-2440) has live caterpillars in season as well as various displays of local insects and other critters. You won't be able to see the adult moths, though, as the cocoons are returned to the forests.
Anbonia (アンボイナ amboina). A very beautiful — but also very poisonous — seashell. See here for more information on how to watch out for them.
Scuba diving is without a doubt the main draw for most visitors to Yonaguni. However, the island's location in the middle of the open sea without protective reefs means that waves can be high and currents can be strong, so most diving here is drift diving and many of the more interesting dive sites are only accessible to experienced divers.
Open Coast Travel. Los Angles, CA, tel. 1-310-433-6653, . Open Coast Travel is the only US based travel agency specializing in guided scuba tours to Yonaguni for western travelers. All bilingual guides have lived in Japan.
Yonaguni Diving Service. Kubura, tel. 0980-87-2658, . The oldest and largest dive shop on the island, quite professionally run: they will cater to your experience level and will not head out to sites if the weather does not permit (in which case your money is refunded). Two boat dives start from ¥12,000, full gear rental for a day is ¥6,500. No credit cards accepted and only limited English spoken. Quite popular, so book ahead.
Reef Encounters International. Chatan, Okinawa, tel. 090-1940-3528, . Doug Bennett has lived in Okinawa for 12 years, and is an expert on diving the Yonaguni monuments. He will help you organise your trip and guide you during the dive. Trips are very reasonably priced and Doug speaks both English (native) and Japanese.
Exploring the underwater ruins
Yonaguni's unique attraction for archaeologists and divers alike are the mysterious underwater ruins (海底遺跡 kaitei iseki) which lie off the southern coast of the island. A single platform 100 by 50 meters wide and up to 25 meters tall, seeming carved out of solid rock at perfectly right angles and dated by some to be 8000 years old, the technology required to build them here doesn't seem to match any known timeline of human history. Some maintain that they are the product of the lost Continent of Mu or even alien artifacts, while the most boring explanation would be that they are merely the product of strange geological processes — although the (apparent) hallways and staircases, as well as what appear to be regular rows of holes dug for moving rock and even what some take to be a form of writing on the walls, would appear to defy this.
Seeing the ruins, however, takes some time, effort and skill: the area is notorious for its currents and not suitable for beginning divers, although several diving shops run one-day crash courses that culminate in a guided tour of the ruins. For those with the requisite skills (PADI AOWD or more), a day's diving starts at ¥12,000. Note that the ruins, some 20 minutes by boat from Kubura, are usually only accessible when they are on the leeward side of a north wind and the currents are not too strong, so you'll also need some luck just to get here.
Wind conditions permitting, SAWES can also arrange glass-bottomed boats to make the trip for ¥5000/head if there are five or more passengers (or you can charter the whole boat yourself). Don't expect to see very much, however, as the ruins are at a depth of 5 to 20 meters.
In addition to the ruins, Yonaguni is also famous among Japanese divers for its hammerhead sharks, which congregate around the island and can be spotted on most dives in the cooler winter season (December-February). Yonaguni is also pretty much the only spot in Japan where it is possible to spot the giant whale shark, the largest of them all, although sightings are quite rare.
Much of the southern coastline is dotted with caverns, caves and underwater rock formations, which make for spectacular but, again, slightly challenging diving. Daiyati and the Temple of Light are particularly well-known spots that bear more than slight resemblance to Swiss cheese.
Other events of note on Yonaguni include:
Swordfish Fishing Competition (カジキ釣り大会 Kajiki-tsuri taikai), . Yearly in July.
Yonaguni Marathon (一周マラソン大会 Isshu Marason Taikai), . Every November. Despite the name, the race is either 10 or 24 km (around the island), not a full marathon.
The most popular Yonagunian souvenir by far is hanazake liquor, see Drink for details.
Ōasa Shoten (大朝商店). One of Kubura's two general-goods stores. Has a pretty good range of hanazake tucked away in the back.
Yonaguni Kaien (与那国海塩) . Located near the beach in Higawa, this store sells salt harvested from Kuroshio Current. The best stuff comes in big crystals several millimeters in size, and supposedly tastes somewhat sweet.
While there are a few small restaurants in Sonai and Kubura, most visitors opt to eat breakfast and dinner at their lodgings and lunch at their diving service.
Shokujidokoro Hiko (食事処 彦), Kubura. The only restaurant in town. Open 9 AM to 10 PM daily except Tuesday.
Maruki Shokudo (マルキ食堂), Sonai, tel. 0737-82-2256. Famous far and wide for its chomei-so soba (長命草そば), which contains a local grass reputed to extend longevity.
Yonaguni is best known for hanazake (花酒), literally "flower sake", a drink nowhere near as dainty as you might expect from the name: it's the local 60° awamori and tradition demands drinking it straight, without even an ice cube to ease the pain. The best known brand is Donan (どなん) and the other labels brewed on the island are Yonaguni (与那国) and Maifuna (舞富名, meaning 'clever person' in the local dialect). You can visit the breweries of all three in Sonai, sample a little, and learn about brewing methods. It's fairly steeply priced though, as a 600ml bottle of the stuff will set you back over ¥2000; and you need to add a few hundred yen if you want the traditional protective straw coat for your bottle. Cheaper and marginally less lethal 43° and 30° versions are also available.
Komine Ryokan (小嶺旅館), Sonai, tel. 0980-87-2211.
Minshuku Omoro (民宿おもろ), Sonai, tel. 0980-87-2419. ¥4500. No bathrooms in the rooms, as it's a minshuku. You can take a bath between 4:00 - 8:00 PM, although they'll usually let you take a bath outside of these times if you ask. Private rooms, nice meals also included. Washing machine costs ¥100. No phones in rooms, but there's a green-phone (public telephone) in the lobby you can use. Be warned, though, that there is a danger of theft because there are no keys to the rooms.
Minshuku Sakihara (民宿さきはら), Sonai, tel. 0980-87-2976. ¥5000; the interior is much better kept than the backpacker-style Omoro but the food may or may not match up. Amenities include a large television and a small manga library; ideal for elderly visitors not used to roughing it.
Yoshimaru-sō (よしまる荘), Kubura, tel. 0980-87-2658. Operated by Yonaguni Diving Service, this standard-issue minshuku offers shared lodging in Japanese-style rooms for ¥5000/3500 with/without meals, ¥1000 extra if you want your own room. Expect some noise in the evenings from boozing divers, but it's lights-out by 11 PM.
Ailand Resort, tel. 098-941-2323, . This is a newer hotel (2007), with a pool, bath house, and restaurant. Close to the airport. Very attentive staff make it very nice. Without meals it is ¥15000 per night.
Okinawa's favorite bogeyman, the habu snake, is absent from Yonaguni. The main danger here is the ferocious currents, particularly on the north coast, so check conditions before swimming. Also, you'll have to watch out for anbonia, which, although a very attractive-looking coneshell, is very poisonous. Anbonia are about 10cm long, have a spiral shell, and will actually stab you with a harpoon-like appendage that they shoot out, and the sting can be deadly.
There are no banks on Yonaguni, but you can withdraw money from the ATMs at the post offices in Sonai and Kubura.
Broadband Internet and net cafés have yet to reach Yonaguni, but most diving and lodging enterprises on the island have dialup accounts and will let you borrow them for a moment if asked nicely.
You're at the end of the earth now — unless you can score a seat to Taiwan, the only way out is back where you came from.