El Salvador is a republic in Central America, bordered by Honduras to the north, Guatemala to the west, and the Pacific Ocean to the south. It is the smallest but most densely populated country in the region. The nation's physical landscape is contrasted by low fertile plains along the Pacific coast, and volcanoes, mountains, and forested plateaus in the interior. Human settlement dates to the arrival of the Pipil people to the west and the Lenca to the east, prior to incursions by the Mayans. European contact was first made with the Spanish admiral Andrés Niño in 1522 who led an expedition to the region. Spanish Conquistadors led by Pedro and Gonzalo de Alvarado arrived in 1524 and were met with resistance which lasted until 1537, with the strengthening of the garrison town of San Miguel. The early 19th century was marked by a number of independence movements and insurrections, claimed in 1822, but not formerly recognized by Spain until 1865. El Salvador formed part of the Greater Republic of Central America, in political union with Nicaragua and Honduras until 1898. The capital and largest city is San Salvador. The population of El Salvador in the 2009 census was 5,744,113.