Keystone offers a variety of on-mountain summer activities for the whole family. Whether you want a good workout, desire some nice views, or are just looking for a good lunch option, Keystone has you covered. Rent a bike and explore the variety of trails Keystone Mountain has to offer. Take the Summit Express to the top of Dercum Mountain and enjoy panoramic views of Lake Dillon and the Ten Mile Range. Make a full afternoon of it and enjoy lunch at the Summit House. Prepare for your summer getaway now by setting up your activity of choice before you arrive.