The largest freshwater lake by volume is Lake Baikal, located in Siberia, Russia. This ancient lake contains approximately 20% of the world's unfrozen surface freshwater and is known for its remarkable depth, reaching over 5,300 feet (1,600 meters). It is also home to a diverse ecosystem, including the endemic Baikal seal. The lake is a UNESCO World Heritage site and is renowned for its unique biodiversity and stunning scenic beauty, attracting researchers and tourists alike.