Horse Island, at 17 acres (69,000 m²), is the largest of the Thimble Islands

Thimble Islands

Ghost Island redirects here. For the island in Japan, see Hashima Island.The Thimble Islands is an archipelago consisting of small islands in Long Island Sound, located in and around the harbor of Stony Creek in the southeast corner of Branford, Connecticut.The archipelago of islands made up of...

 off Stony Creek

Stony Creek, Connecticut

Stony Creek is an affluent, shorefront section of Branford, Connecticut, centered on a harbor on Long Island Sound, in the southeast corner of the town. Stony Creek residents feel it has its own distinct feeling, that of a small village with a traditional timeless and quaint charm...

, a section of Branford, Connecticut

Branford, Connecticut

-Landmarks and attractions:Branford has six historic districts that are listed on the U.S. National Register of Historic Places . These include buildings in Federal, Arts and Crafts, and Queen Anne styles of architecture...

. It is owned by Yale University

Yale University

Yale University is a private, Ivy League university located in New Haven, Connecticut, United States. Founded in 1701 in the Colony of Connecticut, the university is the third-oldest institution of higher education in the United States...

 and is maintained as an ecological

Ecology

Ecology is the scientific study of the relations that living organisms have with respect to each other and their natural environment. Variables of interest to ecologists include the composition, distribution, amount , number, and changing states of organisms within and among ecosystems...

 laboratory

Laboratory

A laboratory is a facility that provides controlled conditions in which scientific research, experiments, and measurement may be performed. The title of laboratory is also used for certain other facilities where the processes or equipment used are similar to those in scientific laboratories...

 by Yale's Peabody Museum of Natural History. It was purchased and donated to the university in 1972 as a convenient addition to the Yale Coastal Field Station in nearby Guilford

Guilford, Connecticut

Guilford is a town in New Haven County, Connecticut, United States, that borders Madison, Branford, North Branford and Durham, and is situated on I-95 and the coast. The population was 21,398 at the 2000 census...

, which has its own dock and boats. Since then, however, the thrust of biological

Biology

Biology is a natural science concerned with the study of life and living organisms, including their structure, function, growth, origin, evolution, distribution, and taxonomy. Biology is a vast subject containing many subdivisions, topics, and disciplines...

 research at Yale and elsewhere has turned in the direction of molecular biology

Molecular biology

Molecular biology is the branch of biology that deals with the molecular basis of biological activity. This field overlaps with other areas of biology and chemistry, particularly genetics and biochemistry...

, and research conducted on the island is less active.

A large house on the island has been kept in good repair and can serve as a base for experimenters or others remaining on the island for overnight stays or longer.

The origins of the island's name are not known. Some say that at some point a cargo of horses may have found its way to the island from a capsized or wrecked ship

Shipwreck

A shipwreck is what remains of a ship that has wrecked, either sunk or beached. Whatever the cause, a sunken ship or a wrecked ship is a physical example of the event: this explains why the two concepts are often overlapping in English....

, but no physical or documentary traces of such an event exist.