Bordered by Mexico to the north and west, Belize to the northeast, the Pacific Ocean to the southwest, the Caribbean to the east, and Honduras and El Salvador to the southeast, Guatemala has a wide range of ecosystems from mangrove forests to beaches to mountains. The Mayans, the largest pre-Columbian civilization in the country, settled extensively here, and ruins are concentrated around Petén. Around 40% of the country's people are indigenous, primarily K'iche', Kaqchikel, Mam, and Q'eqchi. Spanish expeditions to the country began in 1519, and much of the architecture, and primary language, reflect the influence of the Spanish colonization that went on until 1821. Matador has information on volunteering in Guatemala, exploring the Rio Dulce biosphere reserve, learning to study Spanish, and hiking Volcano Pacaya.