4 of us rented bikes at University Cycles and then drove from Boulder to Lyons at the suggestion of one of the Ben's at the bike shop. He showed us on a map where to go and what to expect. The initial part of the ride was hard, but that was partially because we were not used to the altitude and also, gulp, our ages. The 30 year old did not have a problem but the late 50 and early 60 year olds did. The scenery was spectacular with blue skies that only Colorado can produce. Over all the ride was a solid intermediate ride with climbs, floaty parts and switchbacks.