Manatee Springs. A huge <a href="https://en.wikipedia.org/wiki/Karst_spring" class="extiw" title="en:Karst spring">karst spring</a> in <a href="https://en.wikipedia.org/wiki/Manatee_Springs_State_Park" class="extiw" title="en:Manatee Springs State Park">Manatee Springs State Park</a>, near <a href="https://en.wikipedia.org/wiki/Chiefland" class="extiw" title="en:Chiefland">Chiefland</a>, Florida, USA
<a href="//commons.wikimedia.org/wiki/User:Ebyabe" title="User:Ebyabe">Ebyabe</a>
CC BY 2.5
<span class="int-own-work" lang="en">Own work</span>