The Pits!

I've seen tar lakes before,  but haven't seen anyone swimming in them before :).   Pitch Lake is the largest natural asphalt lake in the world located in La Brea, Trinidad.   It's a little less than 100 acres and is about a whooping 246 feet deep.  -The lake is not only a tourist attraction, but it is still mined for it's asphalt to the islands.  Pitch Lake was discovered by Sir Walter Raleigh in 1595 and found immediate use for the asphalt.  When he realized he couldn't smoke it,  he used it to chalk his boat.  He referred to it as "most excellent good.. It melteth not with the sun as the pitch of Norway".  Asphalt from this lake has been used all over the world, including the streets of New York City.

Scientists believe the source of the tar comes from being at the intersection of two plates. When they move they crush oil infused rocks, which percolate to the surface. This is combined with volcanic activity, which produces the phenomenon.  There are folds in the surface, which fill with water. These folds fill with water and create a natural swimming pool.  Yes, pools in which you can swim :).  Most of the lake is safe for walking, however some areas are unsafe and you can sink into the tar.  Another surprise of the lake is the presence of life.   One can find osprey, vultures and other birds enjoying themselves by the water.  The swap adjacent to the lake was filled with lilies and minnows were actually living in the pools formed on the lake.