This region comprises Cape Cod (Barnstable County), the South Coast counties of Bristol and Plymouth, and the islands of Nantucket and Martha's Vineyard. It is an area steeped in history, as some of the oldest settlements of the Northeast are in this region: Plymouth, New Bedford, Fall River, and Provincetown, among others, date from the 1600's.

Cape Cod is known for its unspoiled beaches, quaint villages, historic sites, lighthouses, countless festivals, and its unusually balmy weather. Because of the moderating influence of the ocean on virtually all sides, the Cape is situated at the northernmost limit for growing such warmth-loving plants as camellias and magnolias. Barnstable is the largest town on the Cape; Provincetown, at the far northern tip of the peninsula, is the site of the Pilgrims' signing of the Mayflower Compact.

To the south of the upper Cape, across Nantucket Sound, are the islands of Martha's Vineyard and Nantucket. The latter, one of the most popular summer resorts in the Northeast, quintuples in population every summer. It also boasts the highest median property values of anywhere in Massachusetts. Martha's Vineyard, to the west of Nantucket, is similarly a highly popular, and highly expensive, summer colony which experiences an even greater summer boom: from a population of 15,000 year-round, it can swell to over 100,000 in the summer months.

To the north of the upper Cape, and across Cape Cod Bay, lie the mainland counties of Plymouth and Bristol. Together, these composed the main areas of Puritan settlement within the original Plymouth Colony. It is much less densely-settled than the Boston metro area to the north, characterized instead by villages and small towns, including such historic seaports as New Bedford and Fall River.