The second-largest island is Conanicut; the third-largest is Prudence.
Block Island lies about 12 miles (19 km) off the southern coast of the mainland and separates Block Island Sound and the Atlantic Ocean proper.
A rare type of rock called Cumberlandite is found only in Rhode Island (specifically in the town of Cumberland) and is the state rock.
In 1638 (after conferring with Williams), Anne Hutchinson, William Coddington, John Clarke, Philip Sherman, and other religious dissenters settled on Aquidneck Island (then known as Rhode Island), which was purchased from the local tribes who called it Pocasset."State of Rhode Island and Providence Plantations" is the longest official name of any state in the Union.In recent years, the presence of the word plantation in the state's name became a sufficiently contested issue that the Rhode Island General Assembly voted on June 25, 2009 to hold a general referendum determining whether "and Providence Plantations" would be dropped from the official name.Rhode Island's forests are part of the Northeastern coastal forests ecoregion.Narragansett Bay is a major feature of the state's topography. The largest is Aquidneck Island, shared by the municipalities of Newport, Middletown, and Portsmouth.