Hiking the hills of Griffith Park alone after dark is, unfortunately, ill-advised. Happily, Sierra Club's Angeles Chapter has your back, offering group hikes of varying difficulty during the week and on weekends — and, once a month, a special moonlight hike. These treks are no secret: Between 150 and 250 trailblazers usually show up for each excursion during the warmer months, the more serious ones armed with a sturdy set of boots and poles. (Difficulty levels are numbered: 1 for beginners, 6 for — let's face it — those in better shape.) Led by experienced Sierra Club volunteers, the hikes are two hours long, exploring all 53 miles of the park's trails and changing each week to keep things interesting. Most hikes stop at a high point to give participants a chance to enjoy city views. From up high, even the 5 freeway takes on a mystic quality, the cars streaming around its curves in waves of tiny white lights. "This is a fantastic way for people to enjoy the park," says Councilman Tom LaBonge, who takes in a hike from time to time. "It's activities like this that make our city great." Damn straight, Tom.