From the web about Ginak:
Jinack Island (also spelt Jenack, Ginak & sometimes known as Paradise Island) is located off the north bank of the estuary of The Gambia River, separated from the mainland by the Niji Bolon and is part of the National Park of Niumi which is a marine protected delta area and is aiming to be an eco-tourist holiday destination. The park was established in 1986 and has an area of just over 4,900 hectares (49 sq. km) with (geographical coordinates: 13.30°N 16.30°W) and its boundaries start from Barra Point right up to the Senegalese border at the National Park of Saloum in Senegal then east to the tributary of Masarinko Bolon. The island itself has over 11 kilometres of unspoilt, fairly shallow beaches which are often visited by dolphins.

To get to the island you take a ferry from the port of Banjul to Barra which costs less than 50 pence. From Barra you then take a local taxi heading towards Fass then go left at Kanuma into the park. There are a couple of villages in the area: Jinack Kajata and Niji. It is possible to make a day-trip excursion there from Kololi resort if you set out fairly early in the morning.

A major part of the park encompasses several habitat types such as dry savannahgrasslands, coastal scrub, and woodland which is on an elevated rocky plateau which has the Masarinko . Bolon tributary dividing it. The park itself is riddled with wetlands, thick vegetation, fresh-water marshland, tidal mud flats, mangrove swamps, farmland and lagoons.

The stones sizes and circular shapes do vary from 10 to 20 stones with sizes from 4 to 6 metres across. Though they were burial sites the stones themselves are of a younger age than the graves. The average height of each stone column is 5 feet 9 inches. The 11 large concentration of circles have puzzled many a traveller over the centuries and have been the subject of dozens of archaeological excavations since the 1800s. Excavations were made on them earlier this century but none came closer to laying bare the whys and wherefores of the site than the one carried out about over 30 years ago which revealed their age. What has been found are iron weapons, arrow and spearheads, knives, pottery vessels and bronze ornaments

The stones were cut out of laterite that occurs in large quarry outcrops in this region and then shaped with iron tools into cylindrical or polygonal shapes. A museum situated at the “Stone Circles” in Wassu Central River Division was opened in 2000. Hundreds of stone circles can be found in The Gambia and Senegambia region. They are part of a geographical grouping of over 1,000 monuments in a wide strip measuring 62 miles wide and along 217 miles of the Gambia River.

This sacred site was declared a National Monument in 1995 and on the 21st July, 2006 93 monuments in the Senegambia region (Sine Ngayène, Wanar) were declared by UNESCO to be a World Heritage Site.