Explore Aspen with ACES! Hire an ACES Naturalist Guide, available by the hour, to lead you on adventures and activities around the Aspen area on your own schedule. Trip options are below and in the menu on the left. Basic fees for private, guided hikes are $50 per hour per guide, with a two hour minimum. A snack or lunch can be provided for an additional cost. Please call Jim Kravitz at 970-925-5756 x103 for more information and to reserve your guide or click here. 48-hours notice recommended for tour reservations. If you call after 5pm your call will be returned by 9am the next business day. All tours led by a certified interpretive Naturalist.