Hello, we're a party of two French-Canadian climbers that would like to climb in Colorado Rockies in either late spring or early summer 2019 for a approximately a two weeks trip. However we had never climbed in US Rockies and would like to get some advices/tips on best suggested routes to ascent summits, and suggested time of year for best climbing. For alpine route, we're comfortable with Class 4 climbs (average 5.5-5.6 route on rock) and grade 4 ice climbing. We would like to avoid crowded period. Is there any good guide book for route description. thx for your input.