Christopher Columbus sailed off the coast of Guyana in 1498 but it was not until a century later that the  first Europeans settled in the area. Sir Walter Raleigh visited the territory in 1595 and this was followed by several unsuccessful attempts to establish permanent settlements. The Dutch finally succeeded in 1616 with the establishment of a settlement at Kyk-over-al on an island in the Essequibo River where the remnants of a fort can still be seen. A number of other settlements later sprang up in Essequibo. A  second colony was carved out in Berbice when a settlement was established there in 1627.  Subsequently, the colony of Demerara was also settled by the Dutch. During the 18th and 19th centuries, these three colonies changed hands several times. The British seized them from the Dutch in 1781 but lost them to the French six months later. The French held them for two years before restoring them to the Dutch in 1783. In 1796, the British again captured the colonies but handed them back to the Dutch in 1802. The British recaptured them in the following year and in 1831 united them as the Colony of British Guiana. They ruled the colony until May 1966 when it became an independent state within the British Commonwealth of Nations. On February 23, 1970, Guyana became a Cooperative Republic within the Commonwealth.