A rimless, many-spoked wheel superimposed upon the islands depicts the relationship of New Providence, where the capital, Nassau, is located, to the other islands (out islands, or the Family Islands, as the government prefers to call them) ; it also depicts the isolation of the individual islands. Nassau is a magnet for people from the out islands who seek both residence and employment. The second-largest city is Freeport, on the island of Grand Bahama (population: 41,035); like Nassau, it is a tourist center. The third-largest settlement is Marsh Harbor on Abaco Island. Most settlements are villages of scattered houses located near the shore (e.g., the settlement of Long Bay Cays consists of villages spread out over a distance of 11 kilometers). Nucleated villages are found on offshore cays such as Green Turtle Cay and Abaco. Mail boats, which also carry supplies and passengers, link the settlements to Nassau but not directly to one another.