Okay I am lost at the Switchback thing so what's the list of possibilities? I will be so mad if it's just a term for the task though.
Extracted from Wikipedia:
A hairpin turn (also hairpin bend, hairpin corner, etc.), named for its resemblance to a hairpin/bobby pin, is a bend in a road with a very acute inner angle, making it necessary for an oncoming vehicle to turn almost 180° to continue on the road. Such turns in ramps and trails may be called
switchbacks in American English, by analogy with switchback railways. In British English 'switchback' is more likely to refer to a heavily undulating road—a use extended from the rollercoaster and the other type of switchback railway.
So in simple words: A switchback is a very acute turn in trails/ramps in America. A switchback is a roller-coaster shaped road in Britain. But since it's America, we're going with the hairpin, whose angle is so small the turning for vehicles is large. Now we just need to intepret it to make it The Amazing Race-ish.