I noticed this problem as well. I live in Ithaca, and crossing one of our many gorges generates grades of +/- 150% (as an example, try starting at "Arts Quad, Ithaca, NY" and ending at "Bess Brown Center, Ithaca, NY").
Seems like it would be a little bit tricky to try to systematically identify steep ravines like this in Google's elevation data, but it's certainly an interesting problem.
Seems like it would be a little bit tricky to try to systematically identify steep ravines like this in Google's elevation data, but it's certainly an interesting problem.