In Uncharted 2: Among Thieves, you find yourself within a city in Nepal where you continue your search for Shambala and the Cintimani Stone. When you find the second group of enemies you can see a street sign which says "Hotel El Dorado".

​

This is a reference to the mystical artefact Nathan Drake was looking for in Uncharted: Drake's Fortune which was called The El Dorado which became known as the golden man.

​

This was one of the first references within Uncharted 2 to mention it's predecessor.