Uzbekistan is a dry, landlocked country. It is one of two doubly landlocked countries in the world (that is, a landlocked country completely surrounded by other landlocked countries), the other being Liechtenstein. In addition, due to its location within a series of endorheic basins, none of its rivers lead to the sea. Less than 10% of its territory is intensively cultivated irrigated land in river valleys and oases, and formerly in the Aral Sea, which has largely desiccated in one of the world's worst environmental disasters. The rest is the vast Kyzylkum Desert and mountains.