The largest river of the Republic of Armenia is the Araks, which lies on the countries border with Iran and a large part of the border with Turkey.

Its major tributaries are the Akhurian, Kasagh, Hrazdan, Azat, Arpa, Vorotan and Voghdji rivers.

The largest rivers in north west part of the country are the Debed and Aghstev, while smaller ones include the Dzoraget and the Pambak.

There are not very many lakes in Armenia: there is one very large lake called Lake Sevan and there are more than 100 small mountain lakes.

None of them, except Sevan and Lake Arpi, have yet been extensively studied.

The water resources of the lakes amount to about 39,300 million cu m, Sevan holding most of this, nearly 39,000 million cu m (before the drainage it had almost 58,000 million cu m).