The natives on the island that Columbus first landed on called it Guanahani. Samana Cay was first proposed to be Guanahani by Gustavus Fox in 1882, but the predominant theory for most of the 20th century gave the honor to San Salvador Island (see the Guanahani article for a list of other candidates). However, in 1986 Joseph Judge of the National Geographic magazine made new calculations based on Columbus's logs, and declared that Samana Cay was indeed the right location. Judge's identification has been controversial.
The island is nine miles long (in the east-west direction) and between 1 and 2 miles wide. Its geographical coordinates are .
Samana Cay had a permanent population during the first half of the 20th century (the ruins of this settlement are still visible on the south side of the island, near the western end), but is today uninhabited. Residents of nearby Acklins Island visit Samana Cay occasionally to collect cascarilla bark, which grows abundantly on the island. The island is about 45 km² in area.