World War II Sites
Hiking & Trekking Surfing SCUBA Diving Kayaking, Canoeing & Paddleboarding Sport Climbing Biking


In 1914, the Empire of Japan claimed Pohnpei and the rest of the Caroline Islands as part of its Treaty of Versailles Pacific mandate. The island was taken with a significant show of force, but without a single shot fired, and would remain a territory of Japan until the conclusion of World War II in 1945.

While the two preceding colonial governments, operated by Spain and Germany, had attempted to impose their authority on the local inhabitants and set-up commercial enterprises, they had hardly been colonial in terms of the number of foreign nationals who made Pohnpei their home. The Spanish “colony” consisted mainly of the governor’s administrative entourage, a contingent of soldiers, and Catholic clergy; true colonists were few. The nation fought a number of losing wars with Pohnpeians during its period of occupancy (1886-1899), and by the end of its tenure, those who remained were forced to more or less barricade themselves within their squalid fort at present-day Pohnpei. The German period wasn’t much more successful. Germany was most interested in setting up trading posts and copra production and didn’t interfere much with the locals for the first decade. The German civilians who lived on the island were businessmen and traders who had worked in the Pacific before coming there. There were more of them than during the previous period, but their numbers were still small.

Japan’s reign was wholly different. The Japanese wanted to expand their empire; establish new, self-sufficient communities for its citizens; and be productive. They formed the first true colony, importing 14,000 Japanese nationals — three for every Pohnpeian. They built schools, taught the locals the Japanese language, started large agricultural operations, and built infrastructure. They meant to stay and to make Pohnpei a real part of the empire. In the 1930s, when war began shaping up, the Japanese began seizing strategic land on Pohnpei and the surrounding islands and heavily fortifying it against invasion. High mountains near the coasts were fitted with powerful coastal guns to protect the reef passages and anti-aircraft guns were placed on hilltops, lagoon islands, and around the town. Caves and tunnels were dug and defensive trenches criss-crossed the ridges and mountain slopes. In the end, Pohnpei only saw action from the air. Instead of invading, the Allied forces decided to bomb the island extensively over the course of a year, destroying most of the important targets in the first month.

While all of the small guns and some of the larger ones were removed after the war, Pohnpei still has a great many interesting historical sites related to the war. There are seven intact 15 cm coastal guns (and one partially disassembled), two 12.7 cm anti-aircraft guns, and scores of tunnels, caves, bunkers, and other structures to be explored.

Where to Find World War II Sites

Pohnpei, Federated States of Micronesia

Dolen Eirike

Dolen Eirike Dolen Eirike (“hill of Eirike”) is a prominent pyramid-shaped peak in Eirike district at the rear of Nett -- easily visible from Kolonia and standing out from everything else ...
Read More
Pohnpei, Federated States of Micronesia

Dolen Nett / Pohnlehr

Dolen Nett Dolen Nett ("hill of Nett") is a steep-sided mountain running the length of the Nett Point peninsula. Leaf-shaped, this peninsula juts north into the lagoon east of Kolonia and ...
Read More
15 cm Japanese naval gun at Dolopwuropwur, Temwen Island, Pohnpei, Micronesia

Dolopwuropwur Gun Battery

Dolopwuropwur Gun Battery The most extensive Japanese gun battery on Pohnpei lies on Temwen’s rounded central hill, Nindol, perched at its 60 meter peak, Dolopwuropwur. Gun Stations The four guns at the summit ...
Read More
Hikers at the summit of Kupwuriso Mountain, U, Pohnpei, Micronesia


Kupwuriso Mountain Kupwuriso, Pohnpei's fifth highest mountain (depending on how you count them), is impossible to miss when driving through eastern U, where it towers over everything, its precipitous slopes clad ...
Read More
Inner gate at the entrance to the subterranean Japanese oil tank complex on Lenger

Lenger WWII Historical Sites

Lenger World War II Historical Sites Southwest Side Subterranean Crude Oil Facility (Pahnlenger) Built beneath Dolen Lenger, the Japanese crude oil storage complex is without question the most impressive of the island's historical ...
Read More

Madolenihmw Bay Area

Madolenihmw Bay Area Dauen Sapwalap / Senipehn Mangrove Reserve Visit the Paddling Around Madolenihmw page for a detailed description of this location and the adventures to be had in the area. ...
Read More
Pohnpei, Federated States of Micronesia

Nahpali Island

Nahpali Island Nahpali is a long, narrow reef island running roughly northeast-southwest and located northeast of Temwen Island in Madolenihmw Municipality. The island is privately owned by the Senda family and ...
Read More
Tanizumi style blast walls around the foundation of a Japanese storage facility for heavy ordnance on Sapwtik Island

Sapwtik Island

Sapwtik Island Sapwtik, which means "small land," is a tiny volcanic island located directly north of Kolonia and 0.5 km northwest of Lenger. Seen in profile, the island resembles a large ...
Read More
Pohnpei, Federated States of Micronesia (FSM)

Sokehs Japanese Sites & Parpwu Waterfall

Historical Sites in Mainland Sokehs "Military Road" Hike / Bike Tour One of the most rewarding routes for Japanese World War II-era historical sites follows a road 0.46 km (0.29 mi) northeast ...
Read More
Sokehs Mountain (Pohndollap), Sokehs Island, Pohnpei, Federated States of Micronesia (FSM)

Sokehs Mountain

Sokehs Mountain Sokehs Mountain or Pohndollap, which means "on the big hill," is a long, mostly flat-topped ridge running north-south along the length of Sokehs Island with a knoll-like summit near ...
Read More

Timwen Men, Dolakapw & Pohn Tehnmei

North Madolenihmw Hikes The northernmost section of Madolenihmw is separated from the rest of the municipality by a range of low mountains that run east-west from Mesihsou to Alohkapw. This range ...
Read More

Adventures >> World War 2 Sites