Old Providence McBean Lagoon National Park covers the southeastern coast of Providencia and protects the island's most biologically rich stretch of reef, mangroves, and shallow lagoons. The park is part of the UNESCO Seaflower Biosphere Reserve, which encompasses the entire San Andrés archipelago and its surrounding waters — one of the largest marine protected areas in the Americas.
The park encompasses Crab Cay and several smaller islets. Entry requires a small fee, paid at the park's visitor center. Kayaking through the mangroves is possible and worthwhile for birdwatching — brown pelicans, frigatebirds, and various wading birds are common. Diving within the park requires a licensed guide from the island's dive operators; the reef drop-offs on the eastern edge are the most dramatic dive sites.