There's a lake that freezes from the bottom up - Apparently.
Lake Natron, located in Tanzania, is a saline lake that freezes from the bottom up due to its high salt content. This process, known as "anti-freezing," occurs when the water's density increases as it cools, causing it to sink to the bottom. The lake's surface can remain unfrozen even in sub-zero temperatures, while the bottom layer can be solid ice. This phenomenon is so unusual that it has led to the formation of unique, mummified birds and bats that sink into the frozen layer and become preserved.