Final answer:
Lake General Carrera, also known as Lake Buenos Aires in Argentina, is the largest lake on the border between Chile and Argentina, nestled in the Patagonia region.
Step-by-step explanation:
The lake that lies on the border between Chile and Argentina, which is the largest in Chile, is Lake General Carrera/Lake Buenos Aires. It is shared between Chile, where it is known as Lake General Carrera, and Argentina, where it is referred to as Lake Buenos Aires. This extensive lake is situated in the Patagonia region and is known for its beautiful turquoise waters and intricate system of caves and tunnels carved into the marble around its shores. The lake spans an area of over 1,850 square kilometers, making it one of the largest lakes in South America. Besides its natural beauty, it is also an important water reservoir for the surrounding regions.