Cay Caulker is 7 km (4 miles) long and only about 600 m (650 yards) wide, at its widest point. As a result of hurricane Hattie, the island was split into two separate parts in 1961, just north of the island's village. Cay Caulker boasts mangroves along most of its coast, while palm trees grow in the interior. Not far off the eastern coast is a beautiful reef that offers some of the world's finest scuba diving, snorkeling and fishing spots. The water around the cay is so clear that underwater visibility can be up to 60 m (197 feet)! There are many colorful tropical fish and the coral is magnificent. Be careful when swimming there from the shore, as there are many boats, shuttling people around.

There are several holiday resorts on Cay Caulker, but otherwise it has a laid-back atmosphere. Cay Caulker is 35 km north of Belize City and 100 km northeast of Belmopan.