Jump on Tom's Thumb for a trail experience that will test your climbing mettle.
From the trailhead parking area, the Tom's Thumb Trail starts just on the other side of the shade facility, complete with restroom and kiosks detailing the local flora, fauna, and geology.
After getting geared up and checking your tubeless sealant (there's plenty of thorns if you deviate from the trail here), head up the trail as it meanders along a wide path through vibrant cholla, saguaro, and flowering ocotillo. While at first the trail winds along gentle grades, soon it steepens dramatically and becomes quite tough. Expect to navigate tight, twisting turns up steep switchbacks peppered with loose gravel and sand. Take breaks and spin where you can along this trail, as the grades are long and you'll regret it otherwise.
After roughly a mile of climbing, you'll finally reach your first true break in the terrain as the trail contours the hillside to reach a saddle. Bear right at the saddle to continue climbing toward Tom's Thumb. When you reach a small sign on your right, head right to pick your way along a tricky section of trail to reach Tom's Thumb, or continue straight to begin the steep descent down the trail's western side.
On the descent, expect the trail to dive steeply through steep switchbacks often covered in plenty of rock and chunk. Take it easy through here, as cacti on both sides of the trail can spell a rough landing for an overcooked turn.
After over 2 miles of brake-smoldering descent, the trail reaches a junction with the Desert Park Trail
and finally eases its grade. From here, the trail begins to contour along the hillside on the way to its terminus at a junction with the Windgate Pass Trail