Some of the Atolls#
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Image courtesy of NASA., under PD
The island chain extends north-south for approximately 880 km (550 mi). The Maldives are the exposed top of a long, narrow submarine ridge whose average height is 1 to 2 m (3 to 6 ft) above sea level.
Most of the atolls have spacious, deep-water lagoons suitable for ship anchorage.