It lies on the shore of 110-acre (45 ha) Lake Mohegan, near Great Camp Sagamore, and was completed in two years.

Previously Durant had built Camp Pine Knot, which he sold to industrialist Collis P. Huntington, due to financial difficulties The camp was built of logs felled on the property, and all iron hardware was forged on site.

In 1896, Durant sold Uncas to J. Pierpont Morgan with 1,100 acres (450 ha).

General and Mrs. George Marshall, as guests of Mrs. Vanderbilt, entertained Madame Chiang Kai-shek at Uncas in 1949.

[2] Mrs. Vanderbilt left Uncas to a foundation, which sold it; eventually it was bought by the Rockland County Boy Scouts who used it as a camp.