The park is accessible only from water. For boat launch information please refer to the Connecticut's Boater's Guide.

Though called Selden Neck, this park is actually an island. Cut off from the mainland in the 1850s, Selden Neck has spent the better part of 160 years on its own as the largest island in the Connecticut River. The island is named after John Selden who was the second owner of the property having purchased it in 1695. It remained in the Selden family for approximately 170 years until the 1860s. In 1889 a partnership bought the property to quarry the islands’ red granite schist for paving stones. These paving blocks were four inches wide, seven inches deep and twelve inches long. These blocks were used for paving the streets of  New York city nearly 130 years ago.

Today the roadless, uninhabited, 607 acre island, bordered to the east by Selden Creek and by the Connecticut River to the west, is roughly a half mile wide and one and a half miles long. Except for the tidal marshes, the island is completely blanketed with lush woodland vegetation. The island tops out at nearly 230 feet in elevation providing some areas of potentially strenuous hiking.

Connecticut State Parks has constructed four primitive camp areas (see map) for overnight stays. Each location invites the camper to explore the island trails, some marked better than others, in search of wildlife, the remains of the farmstead, and a former quarry building’s granite foundation.

A marked trail begins near the Quarry Knob camp site and leads to the quarry area in the southeast part of the island. The trail encounters the old causeway, built to transfer the granite stones from the quarry face to the shoreline for shipment.  Another trail extends northwest to the ruins of old farm buildings and a well.

Lookouts from the trail offer wonderful views of the lower Connecticut River. From these the viewer will quickly understand why the Nature Conservancy designated the lower Connecticut River as one of "America's Last Great Places". Views to the east, opposite Selden Creek, encompass 275 more acres of Nature Conservancy owned land. The quiet of the island is inviting. Listen at night to the wind in the wings of waterfowl passing overhead.

History courtesy of David Wordell's "The Quarries of Selden Neck".