Anyone can make a list of Olympic-style events for geologists (rock breaking, hammer throw, cross-country hiking, vehicle pull, etc.). Earth magazine's Timothy Oleson has done something cleverer and more useful in compiling a decathlon of Great Britain geological attractions (including Giant's Causeway in Northern Ireland). The real Olympic decathlon is performed over the course of two days, but the geological version should be taken at a pace befitting its subject. Two weeks would be rushing; two months would be dawdling. I suggest doing the circuit in two fortnights.
U.S. geological attractions:
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