Falls Canyon is a 1 mile round-trip hike through a rainforest like canyon with a 40 foot waterfall at the end. The trailhead is not marked so you will need to know where it is by measuring distance and looking for trail itself. Lots of poison oak exists on this trail so it is a generally good idea to wear pants and a long sleeve. You should allow 15-30 minutes each way for this hike depending on your pace. The trail is easily visible in some places while others places there is no visible trail for short distances but you will be following the creek the whole time in a narrow canyon which makes it easier to navigate through.
Falls Canyon

Parking is 0.6 miles past the white CNF gate and paved creek crossing, you will see a widening in the dirt road which allows for about 3 cars parallel. The trail starts just before the parking area down towards Trabuco Creek which you will have to cross. Additional parking is available by the white gate.
Distance:
1 mile roundtrip
Difficulty:
Moderate
Time:
15-30 minutes each way
Season:
Spring after a wet winter
Elevation:
Trailhead - 1,492 ft
Lowest point: 1,464 ft
Highest point: 1,681 ft
Waterfall: 1,681 ft
The hike begins with an obvious footpath but is unmarked, the path will take you down into Trabuco Creek which you will cross right away before continuing on the trail into the canyon perpendicular to Trabuco Canyon. This narrow canyon is Falls Canyon so if there is water flowing in this creek then the waterfall will be flowing. You will see a cave/mine on the left side right as you enter the canyon which means you are going the right way. The trail disappears in some spots due to creek crossings, log crossings, or rocks but the trail will re-appear shortly after each time. It would be tough to get lost on this trail since you are in a narrow canyon with steep walls.
You will see the waterfall as you get within about 100 feet of it, the approach will bring you right to the bottom of the falls. There is also a faint path to the right just before the waterfall which will take you above the falls but it is dangerous and not recommended.