When you arrive at the Grand Canyon and pay your entrance fees, the ranger will hand you a packet of information, including the canyon newspaper, The Guide. Inside, you'll find a list of tours and programs led by experienced rangers. For an enlightening and free Grand Canyon South Rim tour, just meet the ranger at the appointed time and place.
Tops on the list of free programs are the evening campfire programs. Geared to the entire family, they cover a host of topics, so even if you attend every night, you won't hear the same program twice. The evening campfire programs take place in Mather Amphitheater, check for times when you arrive in the park.