Nantucket Sound is a body of water located between the islands of Nantucket and Martha's Vineyard in Massachusetts. It is part of the larger Atlantic Ocean and is known for its scenic beauty and recreational opportunities, including boating, fishing, and sailing. The sound is approximately 30 miles long and 10 miles wide, featuring a mix of shallow and deeper areas. It plays a vital role in the local ecosystem and is home to various marine life, making it an important area for both conservation and tourism in the region.