It is possible to find rock climbing in virtually every State of America. However, two States in particular have an abundance of excellent rock climbing, these being California and Colorado.
Rock climbing in California is best known for two world class destinations, these being Yosemite and Joshua Tree.
Yosemite Valley is the most famous rock climbing area in America, which is dominated by the granite big walls of El Capitan, Half Dome and Sentinel. El Capitan at 3,300’ (1,000m) is the largest continuous wall in the United States. The valley is famous for its granite cracks and offers every type of climbing at all grades. The big walls of El Capitan and Half Dome dominate the area, but there are plenty of “smaller” walls that are in fact 500’ (150m) high. Yosemite also offers many excellent granite bouldering opportunities. Generally the best time to climb in Yosemite is in the spring and autumn with the summer usually very hot. However the summer can also be the best time to climb the longer and higher routes plus there is extra daylight at this time of the year.
Joshua Tree is the largest climbing area in north America in terms of number of routes, with over 3,500. The white granite rock provides numerous single and multi-pitch routes and many classic bouldering problems. The Quartz Monzonite granite at Joshua Tree is famously course, thus providing excellent fiction, along with many crack features. Hence the style of climbing is “traditional”, requiring the placing of cams and nuts. The best time to go rock climbing in Joshua Tree is from mid-October through to late April or early May.
Rock climbing in Colorado is incredibly varied with many excellent crags and areas. Big wall and long multi-pitch routes are found in the Rocky Mountains (alpine style routes on granite rock), Flatirons of Boulder Mountain Park (sandstone & conglomerate rock with routes up to 300m long), and deep gorges such as Eldorado Canyon (sandstone with routes up to 300m long) and Black Canyon of the Gunnison (adventure climbing at its best). Add in limestone sport routes at places such as Rifle and Shelf Road, plus sandstone bouldering at Fort Collin’s Horsetooth Reservoir, it’s easy to why Colorado offers the greatest variety of rock climbing in America.
The Rock ‘N’ Road guidebook is an atlas of North American rock climbing areas, and it includes information on every state in the United States of America, 7 states in Canada and some information of about the rock climbing in Mexico. This useful book describes the different crags, style of climbing, how to get there, and general information about the area, though it doesn't describe any individual routes.