Located within the Chalk Sound National Park, this small island is located in the channel which connects Chalk Sound Lagoon with the ocean and Caicos Banks. It's a scenic waypoint when kayaking from within Chalk Sound to the open water on the southern coast of Providenciales.
This small, 40 acre island is uninhabited. Several small scenic beaches are found interspersed between the low ironshore cliffs of the south coast. The highest elevations on the cay are located on the north coast, reaching heights of about 15 feet (4.5m). Mangrove wetlands make up the majority of this cay, a large percentage of which becomes submerged during unusually high spring tides.
The channels surrounding Silly Cay are a haven for bird and marine wildlife. Green herons, yellow-crowned night herons and egrets can be seen in the mangroves, and juvenile lemon sharks and barracudas often hide in the deeper portions of the channels due to the plentiful prey.
Silly Cay was named after early 1900s Irish entrepreneur George Silly, a businessman who started an array of enterprises, including turtle farming, sea-sponge cultivation, and a seafood cannery. The nearby region of Silly Creek is likewise named after him, and is the home to many luxury vacation villas.
Silly Cay is part of the Chalk Sound National Park, however, recent 2016 proposals may result in the removal of the cay from the protected area.
Access is one of the potential limitations to development. Directly to the east is the expansive luxury mansion Emerald Cay, so the natural access from Silly Creek is prohibited. This leaves two other options: a long causeway or bridge across the protected sound and waterway, or a shorter bridge on the western side of the cay across West Mouth, a very long route that would mean extensive road development in the Frenchman’s Creek Nature Reserve.