The tunnel of greenery of this causeway and you have no idea where you are going so you just keep going. The trees you can see are arroyo willows and wax myrtles evidence that a dune complex is 'not just sand'. Both of these species need generous amounts of water to flourish. They are being sustained by Oso Flaco Creek, a 'riparian corridor', which means a bank or area relating to a natural waterway.