Like other islands in the Little Antilles, the islands have a bedrock of young tertiary and quaternary limestones and sandstones. However, Antigua’s southwestern part consists of tertiary, basic volcanoes, which provide a much more hilly terrain than in other parts, with altitudes up to 400 m above sea level. According to COUNTRYAAH, the coast on this part of the island is also higher and steeper, while the northeast coast is known for its low sandy beaches, coral reefs and many small ports. There are no active volcanoes, but earthquakes.
The climate is warm all year round, and the rainfall that the northeast pass brings in is moderate. No actual watercourses are missing, and troublesome drought can occur.
There were five national parks in Antigua and Barbuda in 2009, two of which, Diamond Reef and Palaster Reef, are marine national parks.