Echo Lake is a glacial tarn in the Ruby Mountains, in Elko County in the northeastern part of the state of Nevada. It is located at the head of remote Echo Canyon at approximately , and at an elevation of . It has an area of approximately , and a depth of up to , making it both the largest and deepest lake in the Ruby Mountains. It is the major source of Echo Creek, which after exiting the mountains merges with other streams to form the South Fork of the Humboldt River.