This island has a length of approximately 4 km and is located in the Samae San sub district of Sattahip. This island is approximately 184 km from Bangkok and 50 km south of Pattaya. It is uninhabited and has thick vegetation growing in its centre. The island is only accessible to tourist Tuesday – Sunday between 9:00 am and 4:30 pm. It is closed to tourists for part of the year to allow for natural regeneration.

From Bangkok take the BTS Skytrain to the Eastern Bus station located at Ekamai station. From here you can take a bus to Amphoe Sattahip. Once in the small informal bus station in Sattahip look for a mini bus that travels between sattahip and Chong Samae San, this bus only runs between 5:30am - 6:30pm. In Chong Samae San a 10 minute taxi ride or 20 minute walk can take you to the Natural History Museum.

This island can be reached from the Natural History Museum between Tuesday and Sunday of every week. The boat departure begins at 9.00 a.m and the last boat departs from the island at 4.00 p.m. The boat ride costs about 250 Bht per person. The cost for entry to the island is 40 Bht for Thais and 200 for foreigners. They advise to call ahead to ensure the boats are running.

The island is lined with white sandy beaches and clear, clean waters. The islands are a great place to experience marine biodiversity because of the Royal Thai Navy's conservation initiatives. Plants and animals have been preserved and the island is able to be home to sea turtles laying their eggs, coral reefs, stingrays, moray eels and rare plants. The conservation initiatives have included replanting of mangrove forests and replanting of natural vegetation. With these efforts though there is still little, if any, education given to the tourists on how to properly interact with the natural environment without leaving an imprint. An activity like snorkeling should come with information to tourists on why stepping on reefs are harmful or the need to wash off sunscreen because of chemicals that are poisonous to aquatic life.

Samae San Island was the former location of a fishing village, but the community was removed by the Royal Thai Navy which now controls the island. The island became part of an environmental royal project of Princess Maha Chakri Sirindhorn. The royal projects focused on plant genetics conservation on the island and coral rehabilitation.Many of the former residents, some 1240 families, now live on the mainland shore fishing village.

Visitors are restricted to certain areas of the island and can only engage in activities monitored by the Thai Navy. The island is off limits to casual tourists, meaning that all visits must pre-book through a travel agent. Activities on Koh Samae San try to incorporate elements of ecotourism including fishing with locals, swimming, snorkeling, hiking and bicycling on trails. Tourists can also visit the Natural History Museum located on the mainland