What is the deepest lake in the world?

• A. Caspian Sea
• B. Crater Lake
• C. Lake Victoria
• D. Lake Baikal

Answer: (D)

The concept here is how deep a lake is measured from its surface to its bottom. Lake Baikal holds the record for the deepest freshwater lake, reaching about 1,642 meters (5,387 feet). Its extreme depth comes from its location in a continental rift valley that grew over millions of years, creating a very deep basin that fills with ancient, clear water. Because of this great depth, Baikal contains a huge portion of the world’s unfrozen freshwater and hosts many unique species found nowhere else.

Crater Lake, while very deep for a crater lake, is about 590 meters, much shallower than Baikal. Lake Victoria is also relatively shallow, well under 100 meters. The Caspian Sea is deeper—over 1,000 meters—but it’s classified as a sea (and is brackish, not a freshwater lake), so Baikal remains the deepest freshwater lake.