What are the best free activities and attractions to enjoy in Grand Canyon National Park in Arizona, allowing visitors to experience the park’s stunning landscapes, wildlife, and natural beauty without spending extra money? Could you provide a comprehensive guide to the top free things to do, including iconic viewpoints, hiking trails, scenic drives, and unique experiences such as sunrise and sunset views, ranger-led programs, and wildlife watching, while also offering tips on how to make the most of a budget-friendly visit? Additionally, what are the best spots for photography, relaxation, and exploration without needing to pay for guided tours or special events?