My wife and I decided to thru-hike the Otay River Valley, starting at Otay Lakes County Park all the way to the Palm Ave Trolley Station near I-5. The hardest part of the hike was trying to figure out how to get started. We ran into a lot of fenced in "No Trespassing" areas, but we talked to some Park employees and they authorized us to go into those areas since we were hiking. We also learned that the Otay River Valley is currently being developed and will be open to the public in another year or so. In that light, my wife and I felt lucky to be one of the first to go through.The hike was only difficult because of the distance involved. There are a number of informal trails on both sides of the river with many places to go from one side to the other. Sadly, there are a number of homeless people living in tents and trees all along the river.