Marco Island  is a small sea island, or barrier island, on the Gulf Coast of the United States. Located 20 miles south of Naples in Collier County, Florida it is 198 nautical miles to Havana. It is the largest of the Ten Thousand Islands. Marco Island is a beach and boating resort island with a small-town character. It is home to the JW Marriott Marco Island Beach Resort and Hilton Marco Island Resort, a golf club, a yacht club, a country club, several parks, and nature areas. The six-mile crescent beach on Marco Island is among the widest in Florida and features bright white, sugar sand and bountiful shelling opportunities. There are two public access locations with parking and amenities (Tigertail and South Beach), a private beach complex for residents (Residents’ Beach) and a private parking area for residents (Sarazen Park at South Beach), and two other public access points (with no amenities). Access to offshore island beaches, such as Keewaydin, are conveniently accessed by boat or tours. Marco is close to the shopping and restaurants of Naples.

Marco Island is a principal city of the Naples–Marco Island Metropolitan Statistical Area. The population was 15,760 at the 2020 census.[citation needed] It was ranked as the sixth most affluent metro area in the nation.[citation needed] The population more than doubles in size during the winter season. A daily ferry connects the island to Key West.

Marco Island is the largest barrier island within Southwest Florida’s Ten Thousand Islands area extending southerly to Cape Sable. Parts of the island have some scenic, high elevations relative to the generally flat south Florida landscape. Like the city of Naples to the north, Marco Island has a tropical climate; specifically a tropical wet and dry or savanna type (Aw under the Köppen system). It is known for its distinct wet and dry seasons, with most of the rainfall falling between the months of June and October.