A difficult hike on Blacketts' Ridge Trail begins at 8:30 a.m., Friday, Nov. 2; free. The hike is 3 to 4 hours over 6.2 miles with a 1700-foot elevation gain. Children younger than 18 must be accompanied by an adult. Call 429-4492 for reservations and more information. Visit sabinonaturalists.org
for information about other, regularly scheduled Sabino Canyon hikes.