One of Glendora's quiet luxuries is that the mountains start where the town ends.
You don't drive an hour to go hiking here — you drive a few minutes. The San Gabriel Mountains rise straight up behind the north edge of town, and the trailheads are close enough that you can be up, out and back before the pool warms for the day. These are the five we point guests toward, roughly easiest to hardest.
1. South Hills Wilderness Area — the easy one
On the valley side of town, the South Hills give you gentle, rolling trails with views over the basin. It's the right call for an easy walk with the family, an evening stroll, or a first outing to shake off the drive in. Nothing steep, nothing technical.
2. Glendora Wilderness Park & Big Dalton Canyon — for the shade
Head up Big Dalton Canyon Road and you're into a different world: shaded trails that follow the creek past bridges and a campground. The Keiser Trail is the pick when you want trees over you rather than sun. On a hot day this is the one — cool, green and easy underfoot.
Start early, carry water, and you'll be back at the pool before the heat sets in.
3. The Colby Trail — the local classic
The Colby Trail climbs out of the north end of town and rewards you with wide views back across the San Gabriel Valley. It's mostly uphill and a little rocky in places — a proper morning's out-and-back that earns the swim afterward. Go at first light in summer.
4. Mystic Canyon & the Dalton network — to go longer
If you want more, the canyon trails above Big Dalton link up into longer routes through Mystic Canyon and beyond. Check current conditions before you commit to a long day; the higher you go, the more the season matters.
5. Glendora Mountain Road — not a hike, a drive
Save this one for the end of the day. The Glendora Mountain Road — GMR to locals — winds up into the mountains behind town, a favorite of cyclists and worth the drive for the overlooks alone. Time it for golden hour and the whole valley lights up beneath you.
Before you head up
- Start early in summer — trails bake by mid-morning, and shade is limited on the exposed climbs.
- Carry more water than you think you need.
- Check trail status and fire-season conditions; access can change through the dry months.
- Then come home to the pool. That part never changes.