Complex sentence: Eddy Merckx said his hour record attempt was "the hardest ride I have ever done", and was set in Mexico City at an altitude of 2,300m (7,550 ft).
Split into simpler sentences: Eddy Merckx said his hour record attempt was "the hardest ride I have ever done". It was set in Mexico City at an altitude of 2,300m (7,550 ft).