Moderately hilly two-hour hike. After parking on the street, it's a short walk up to the true park entrance. This hike works well in either direction, but I will describe the clockwise version. Take the left fork away from the picnic table, up the Mine Hill trail, which soon passes under trees then emerges as it climbs steadily for 0.5 miles up to the bench at the junction with the Guadalupe Trail. Continue up the more moderate slopes. Good views of the city can be had here and there to the left through the breaks in the trees. After 0.9 miles we pass the marker for the Cinnabar Trail, then continue 0.2 miles to the first views of the Guadalupe Reservoir. Make sure you turn right, heading steadily downhill to the dam. (The path across the dam leads to Hicks Road where there is a small amount of roadside parking). Continue on the occasionally steep downhill, listenning for the Guadalupe Creek as the trail makes its way in and out of the trees. After about a mile, the trail climbs up before a sharp turn brings you onto what always feels like the homeward leg. Pass the bench and head downhill. This section has great views of San Jose, and behind it you can usually spot the gleaming white of the Lick Observatory on the Mt. Hamilton Range. Half a mile more brings you to the Senador Mine area, which is dominated by the two large concrete settling towers. Continue anouther 0.2 miles back to where you started.
Wildflower tip: Look for Indian Paintbrush on the right hand side as you approach the Cinnabar trail marker, and you can usually find the first Shooting Stars up on the bank as you make your way towards the dam.