A republic in Central America. It is also the least densely populated with a demographic similar in size to its smaller neighbors. The country is bordered by Honduras to the north and by Costa Rica to the south. The Pacific Ocean lies to the west of the country, while the Caribbean Sea lies to the east. For administrative purposes it is divided into 15 departments (departamentos) and two self-governing regions (autonomous communities) based on the Spanish model. The departments are then subdivided into 153 municipios (municipalities). The two autonomous regions are Region Autonoma del Atlantico Norte and Region Autonoma del Atlantico Sur, often referred to as RAAN and RAAS, respectively. Until they were granted autonomy in 1985 they formed the single department of Zelaya.