Kingsley Lake, Natural lake in Clay County, Florida, US.

Kingsley Lake is an almost perfectly circular lake of about 2,000 acres (810 ha) in Clay County, about six miles east of Starke. Its deepest point is about 100 feet (30 m) inside a steep sinkhole. The lake lies on the edge of the Trail Ridge formation and has a sandy bottom.

Kingsley Lake formed as a sinkhole on the edge of the Trail Ridge formation; some sources call it Florida's oldest and highest lake. By the early 20th century, the surrounding community had a post office, churches, and schools, and the lake's stable, sandy-bottomed basin made it a local landmark.

Local pilots started calling it Silver Dollar Lake after observing its perfectly round shape from their aircraft during navigation training exercises.

About 180 docks line the lake, concentrated on the western half around the small community of Kingsley. Camp Blanding, part of the Florida National Guard, occupies the eastern shore, with a small airstrip just southeast of the lake. The water is about 30 miles northeast of Gainesville and 30 miles southwest of Jacksonville.

Pilots call Kingsley Lake the "silver dollar lake" because its outline is so nearly circular. The lake sits on the edge of the Trail Ridge formation, and its deepest point, about 100 feet, lies inside a steep sinkhole within the lake.