Mount Hopkins loop from Fred Lawrence Whipple Observatory

The Mount Hopkins loop from Fred Lawrence Whipple Observatory is one of those mountain biking routes that truly tests your mettle, offering a difficult 24.3-mile (39.1 km) journey with a substantial 4622 feet (1409 metres) of climbing, typically taking around 4 hours and 34 minutes. This route is best suited for experienced mountain bikers looking for a significant physical challenge and rewarding, expansive views across the Arizona landscape.

What to expect on Mount Hopkins loop from Fred Lawrence Whipple Observatory

Prepare for a continuous ascent as you navigate this wide access trail, which transitions from paved sections near the start to predominantly dirt and gravel roads. The scenery shifts dramatically as you climb, moving from classic desert landscapes with mesquite and ocotillo at lower elevations to juniper and even pine trees higher up. The Fred Lawrence Whipple Observatory, with its distinctive telescopes, serves as a constant, inspiring landmark, offering incredible panoramas that stretch across the Santa Rita Mountains, including Mount Wrightson, and into the distant blue of Mexico. The climb is physically demanding, with average grades around 5-6% and steeper pitches reaching 15-20%, so be ready for sustained effort. The descent is known for being very fast, requiring good bike handling skills.

Planning your visit

Access to the observatory road can be restricted, especially beyond the 7.8-mile (13 km) mark, so it's wise to check current regulations before you go; weekends are sometimes suggested for riding when observatory staff are less present. The visitor center at the base provides amenities and information, making it a good starting point for your Mount Hopkins mountain biking adventure. Be aware that you'll reach altitudes of around 8,500 feet, so elevation can be a factor, and always carry plenty of water for this challenging ride.

Trail details

• Distance: 24.3 miles (39.1 km)
• Elevation gain: 4622 feet (1409 metres)
• Difficulty: difficult
• Estimated time: 4 hours and 34 minutes