Private Islands of Penobscot Bay and Muscongus Bay: With favorable winds and beautiful archipelagos composed of pristine islands and sheltered anchorages, Penobscot Bay and Muscongus Bay are idyllic escapes known to sailors and yachters worldwide. Several hundred privately owned islands provide the quintessential Maine retreat— each a unique, secluded world unto itself. Real estate on private islands forms a distinct subsector of the general real estate market. Many private islands for sale exchange hands among family members, friends, and others with existing close ties to the region. As these islands become more developed, island properties increase in value and cachet. Maine islands for sale include waterfront properties on islands and islands for sale in their entirety, ranging in size from just two or three acres to substantial island "kingdoms."