The largest natural lake in California, Clear Lake is also the oldest. Where other lakes in Northern California have gradually filled with sediment and become prairies, Clear Lake is constantly renewed by the continuing tilting of the lakebed northward, the result of the ongoing collision of tectonic plates. The geothermal hot springs in the lake may be the cause of Clear Lake's claim to having more fish per acre than any other lake in the country.
Cities around Clear Lake include Lakeport, Clearlake, Nice and Lucerne.
