Touristic Islands of Abacos, Bahamas Trip. Abacos Tourism and Marsh Harbour Environment. The Abacos Great and Little Abaco, and their offshore cays are one of the jewels of the Bahamas: a 320km crescent of sand that's a sailor's paradise, a history-buff's delight, a seafood-lover's dream and a bold entry in any diver's wish list. Most Abaconians live in Marsh Harbour, capital of Great Abaco and the only urban area of any size. This bustling 'metropolis' boasts the Out Islands' only stoplight, and its marinas are the launching pad for exploring the surrounding area: the 'Loyalist Cays' Elbow, Great Guana, Man O' War and Green Turtle are all just a short ferry ride away. Named after the 18th-century settlers who came here after backing the wrong side in the American Revolution, they're special places graced by clapboard homes, historic lighthouses, lush mangroves and a unique culture. Offshore, the warm and bounteous Sea of Abaco is studded with stunning coral, and overflowing with marine life..