Dotted with small undulating hills and cliffs that enliven the landscape, Cayo Santa María has an elongated and narrow configuration (just over 13 km long and 1.6 km in its widest portion) arranged from east to west.
Its north coast has extensive beaches (just over 10 km) of fine white sand and velvety crystalline waters of surprising blue-green tones surrounded by a hotel infrastructure harmoniously integrated into the environment that have made it one of the main tourist centers of the Caribbean country. The south, however, is occupied by mangroves and marshes, forming several inlets (La Oliva, Pelo de Oro and Santa María). Its extreme points are Punta del Este de Santa María (East and South), Punta Matamoros (West) and Punta Madruguilla (North).

Even when its beaches are interrupted by low rocky cliffs (farallones) that enhance its beauty, its sandy bottoms and turquoise waters of incomparable transparency make up a continuous whole from Playa Cañón, in the extreme west, to the access channel to the Santa María cove by Cayo Ballenatos.
Its dunes, on the other hand, reach heights close to 7 meters above sea level at Los Delfines beach, serving as a natural viewpoint over the surrounding vegetation.
Given their recent formation and greater relative height, the beaches of the eastern region of the key are in many cases still unstable, disappearing and reappearing in the heat of the restless waves that haunt them almost all year round.
However, Las Gaviotas beach belongs to the Cayo Santa María Fauna Refuge of particular interest due to its particular isolation from the hotel infrastructure, its calm atmosphere, shallow depth and exceptionally calm sea that make it a pool of daunting proportions to the accessed by a pleasant path through the forest.