Poison oak is common, especially on single-track trails. Old mining roads can be steep and tiring. Keep your distance from ruins of the mining era. Watch for mountain bikers - and mountain lions.

Hike suggestions

Easy: The New Almaden Trail from the Mockingbird Hill Lane entrance takes a nice up-and-down route through the woods for about a half-mile to Randol Creek - you can turn back from there or head uphill. A 2.5-mile out-and-back to the Buena Vista Mine site is a bit more rugged, but worth the effort.

Moderate: You can't go wrong on the 6.5-miler in Zack Taich's history hike. It passes all the must-see mining sites, and has expansive views of the Santa Cruz Mountains. Trail head is at the park's Hacienda entrance just past the village of New Almaden.

Hard: For an all-day trek that'll have your feet filing formal protests, grab a map at the Hacienda entrance and hike to the Guadalupe Reservoir on the park's far side, and return. A basic route departing on the Mine Hill Trail and returning on the Randol Trail is about nine miles, but options for ramping up a route to 12 or 15 miles are wide open.