Mysterious ancient city built on coral rocks on the SE corner of Pohnpei. You can either get a boat there (nice approach from the sea) that can be arranged via Pohnpei Surf Club (google them) or drive about 1.5 hr to get there. I will talk about the second method since I did not take a boat. A taxi will cost you US$80 for one person and a bit more for the whole car if more than one person. I went with the taxi driver named Augustine (691)9264085 who is recommended by many on Facebook EPS. For US$80, he can drive you to multiple sites all over Pohnpei for a full day.
I do not suggest you drive yourself due to the complexity of finding one’s way to the ruins from the car parking area. Your taxi driver can guide you to the ruins, especially on a foggy or rainy day when the very rough footpath (around 500m) becomes hazy and unclear. At the car parking area or shortly after, one will be approached by 2 separate locals asking for “entrance fees” of between US$1 and US$3. They are supposedly the local squatters and representatives of the traditional tribal ruler. The footpath is rocky (some parts of muddy) and slippery, and in my opinion, can potentially be dangerous for the elderly. At the end of the footpath is a narrow sea channel by the main ruins. Depending on the tide, the water can be between 20cm and 1 meter or more high, and one needs to wade across it to reach the ruins. The water is muddy so you cannot see the bottom. Dress appropriately. The ruins are definitely WHS-worthy but the access is difficult and the government has not maintained the site.