Buena Vista Lagoon is a freshwater lagoon adjacent to the Pacific Ocean in the South Coast region of Southern California within the North County region of San Diego County.

The lagoon covers 223 acres of wetland habitat and serves as a geographic border between Carlsbad and Oceanside.

Buena Vista Lagoon is managed by the California Department of Fish and Wildlife.

[2] It is home to the Buena Vista Audubon Society Nature Center,[3] and is California's first Ecological Reserve.

Buena Vista also serves as a valuable wetland habitat for migrating bird species during the fall months.