A mountain climber starts a climb at an elevation of 453 feet above sea level. At his first rest stop he has climbed 162 feet, and by his second rest stop he has climbed another 207 feet. It's getting late in the day, so the climber starts his way down. If the climber descends 285 feet, how much does he need to ascend or descend to return to the original starting point?
The climber has ascended a total of 162 + 207 = <<162+207=369>>369 feet.
After descending, the climber is at an elevation of 453 - 285 = <<453-285=168>>168 feet above sea level.
To return to the original starting point, the climber needs to ascend 453 - 168 = <<453-168=285>>285 feet. Answer: \boxed{285}.