The island is separated from the mainland by Barrington Passage, a narrow strait but has been connected since 1949 by a causeway. The largest community on the island is the fishing port of Clark's Harbour. Other communities include North East Point, Centreville, Clam Point, Stoney Island, South Side, Newellton, West Head, and The Hawk.
Following the Acadian Expulsion in the 1750s, the island was settled by the New England Planters from Cape Cod and nearby Nantucket Island were establishing centers for successful fisheries. The waters off southwestern Nova Scotia had been well known to them probably since the days of French settlement in the early 1600’s. While the tides of the Gulf of Maine may have brought a few exploring fishermen from Nantucket to the island, it was an entirely different tide that spawned the eventual permanent English settlement – a political tide.
Many Cape New Englanders took advantage of the offer of 50 acres of land to each male adult who would leave their homes and live on those vacated lands in Atlantic Canada. Cape Sable Island was well known to Cape Cod fishermen and they moved north in 1760 to take advantage of a new life. The Cape Sable settlement soon became, and remains today, an important base for inshore fisheries. It is famous as the birthplace of the Cape Islander fishing boat, a motor fishing boat which emerged about 1905. Ferry service provided transportation to the island in the early 20th century. A causeway was eventually constructed for pedestrian and automobile traffic, opening on August 5, 1949. Today the lobster Fishery is the island's biggest industry.
The island lies in the path of Nor'easters and hurricanes which occur periodically. Cape Sable Island is also prone to bouts of thick fog. Over the years the Cape's storms, and the close proximity of the island to shipping routes, has led to a substancial number of shipwrecks. The most tragic was the wreck of the SS Hungarian in February 1860 with the loss of over 200 lives. A lighthouse was established at the tip of Cape Sable in the next year.
In spite of what might seem to have been major deterrents to permanent settlement, they came and they stayed. There were shiploads of Smiths, Nickersons, Atkinsons, Crowells, Newells, Townsends, Quinlans, Rosses, Swims and many others; their descendants are still here some 250 years later. Archelaus Smith settled in Centerville, Michael Swim at Swims Point in Clark’s Harbour, Newell families in Newellton, Daniel Vinton at Daniel’s Head in Southside, Ross families at Stoney Island – many of these surnames remain very common today.
With the ocean lapping on all sides of the island, the climate is maritime - decidedly cool in summer but winters are considerably more moderate than interior parts of the province. The island is a notable birding destination, being an important migratory stopping point for birds such as the Atlantic Brant and Piping Plover. It is this unique climate, its abundant tidal marshes and the island's geographical location on the north-south flight path of numerous migratory water fowl that has given it the international designation as an Important Birding Area (IBA). The annual Brant Geese fly-by during March and April is developing into a local Birding Event. The tens of thousands of Brant make their spectacular fly by at dusk after spending the day feeding in local marshes. They spend the night bobbing in the Atlantic to the east of the island.