LA river

Most of the people doesn't know LA has a river! It's hidden in a huge concrete pit, crossed by tens if not hundreds of tall, concrete bridges... Right now a symbol of human attempt to control nature and a paradox: while LA is pumping expensive water from tens of miles away, all the rainwater flushes through here instantly into the ocean. Nothing gets absorbed by soil, therefore a need for artificial irrigation and the vicious circle goes on. An impressive symbol of human conceit in the 20th century.