Funafuti is an atoll on which the capital of the island nation of Tuvalu is located. It has a population of 6,194 people, making it the most populated atoll with 57.2 percent of Tuvalu's population. It is a narrow sweep of land between 20 and 400 metres (66 and 1,312 feet) wide, encircling a large lagoon 18 km (11 miles) long and 14 km (9 miles) wide. With a surface of 275 square kilometres (106.2 sq mi), it is by far the largest lagoon in Tuvalu. The land area of the 33 islets aggregates to 2.4 square kilometres (0.9 sq mi), less than one percent of the total area of the atoll.
The capital of Tuvalu is sometimes given as Fongafale or Vaiaku, but the entire atoll of Funafuti is officially the capital. As Funafuti is an atoll, cargo ships can enter the lagoon and dock at the port facilities on Fongafale.