This 16,000-acre expanse may be the largest municipal park in the country, but you won’t find any softball fields or grassy concert venues here. Thanks to mile after mile of secluded Sonoran Desert scenery, visitors to this rugged park can easily forget they’re still in the nation’s fifth-largest city. Superb hiking and mountain-biking trails crisscross the park, including the burly National Trail, which a local mountain biking book dubs “the Teacher of Terror.” Hiking National Trail is easier, but at 14.3 miles each way, you’d better bring a buddy, lunch, and lots of water. The rest of us can drive up to Dobbins Lookout on the scenic and circuitous Summit Road. To get there, just head south on Central Avenue into the park and follow signs.