A presentation titled "The CCC in Saguaro National Park" takes place at 2:15 p.m., Friday, Dec. 3. A presentation about Ironwood Forest National Monument takes place at 3 p.m., Saturday, Dec. 4. Learn about snakes at a presentation at 11:45 a.m., Sunday, Dec. 5. Free with park-use fee of $10 per vehicle; or $5 for pedestrians or bicyclists. Call for more information.