© Christopher Earls Brennen

Hike J5. Green Mountain Canyon


The eastern end of the San Gabriels in the region of Lytle Creek contains some of the most rugged and beautiful canyons in the range. The South Fork of Lytle Creek runs due east from the slopes of Cucamonga Peak and forms the northern side of a dominant ridge, the San Sevaine ridge, that runs east from Cucamonga Peak and overlooks the eastern end of the San Gabriel Valley. Green Mountain Canyon drops dramatically down over the end of this ridge into Lytle Creek and emerges at the rustic Green Mountain Ranch. This hike starts at the radio towers on a highpoint at the end of the ridge and descends the entire length of Green Mountain Canyon with many rappels and downclimbs. It is a dry hike suitable for any time of the year provided the road up to San Sevaine Flats is open (it is usually only closed when there is substantial snow - check with the Lytle Creek Ranger Station).


The hike requires a four-wheel-drive shuttle. From Los Angeles take the 210 Freeway or 10 Freeway east toward San Bernadino and the 15 Freeway north toward Barstow. About 3mi before the intersection of the 15 and 215 Freeways in Devore, exit the freeway where the signs indicate the Lytle Creek recreation area. Drive north past Nealey's Corner toward Lytle Creek and, 1.6mi from the freeway, identify a prominent white metal gate (34o12.10'N 117o26.92'W, elevation 2230ft) at a turn-off on the left. This is the entrance to the San Sevaine Flats road which you will shortly follow. Then continue on up Lytle Creek road for 4.1mi and turn left into the Green Mountain Ranch (5.7mi from freeway). Leave one vehicle here (34o14.03'N 117o29.63'W, elevation 2840ft) and drive back down Lytle Creek road to the entrance to the San Sevaine Flats road.

It is possible to drive a 2WD vehicle up the rough dirt road that climbs up to San Sevaine Flats but it is not recommended; a 4WD vehicle is much preferred. It takes about 40min to drive the 7.5mi to the road junction where the access road to the radio towers forks to the right. Turn right onto that spur road and proceed to the broad, flat parking area at the radio towers (34o12.80'N 117o30.04'W, elevation 5590ft).


The hike begins at the sharp left hand corner in the dirt road just as you turn onto the 5590ft parking area at the radio towers (34o12.80'N 117o30.04'W). From this point hike NE down a wooded slope (there is a rough opening with a berm at the roadside) that soon feeds into a broad, shallow valley. This is very pleasant and easy off-trail walking. The gully gradually deepens and after 50min and 0.5mi you will come to a junction with an equally large gully entering on the right (elevation 4670ft). More easy gully travel follows until, at 4310ft elevation and 2hrs and 0.7mi from the start, you abruptly arrive at the top of a very large drop-off. This is the first and highest rappel in Green Mountain Canyon. It is a drop of about 180ft with a sloping ledge about a third of the way down. The anchor is a stout bush in the rockface on the left. The lower part of this descent could be quite wet if the stream is flowing but normally the stream in this canyon is little more than a trickle. We should also note that it may be possible to bypass this big drop by traversing up and over to the left where a substantial side gully drops down to the bottom.

The first rappel   The last rappel

From here on Green Mountain Canyon is a beautiful and rugged descent, a classic San Gabriel canyon with bands of hard rock and hanging gardens of fractured granite. It is almost brush free. Below the big rappel you enter a narrow slot section with a number of downclimbs before the canyon starts a more rapid descent that begins at 3840ft and 3hr 20min from the start with a broad 30ft cliff that you rappel using an anchor tree on the left. This is immediately followed by a 35ft dryfall that can be bypassed on the left by climbing over some projecting rocks (the climb is somewhat exposed) to access a steep earth slope extending to the bottom of the fall. This in turn is followed by a short 20ft rappel at 3810ft for which we web-wrapped a rock trapped under a large boulder in the middle of the streamcourse.

This brings you at 3780ft and 4hrs from the start to the second largest rappel in this canyon, a two-stage descent just before the canyon makes an abrupt right turn. The descent consists of a 15ft drop onto a streambed platform followed by a steep 50ft slope in a broad bedrock slot. We used a tree anchor about 12ft above the lip on the left to set up a single strand rappel with recovery cord for the 100ft rappel but it may be better to use one of the trees further off on the left to set up a double strand rappel.

Just after the right turn at the bottom of this rappel, the canyon becomes more wooded and there is a 50ft drop created by a large chockstone. To bypass this, climb up on the left and contour over to an easy leaf-filled descent gully. This is followed by about another 20mins of easy hiking before you come (at 3340ft) to a steep 25ft drop into a narrow slot followed by another 20ft drop. These are both readily bypassed by means of an easy ledge on the right that descends to the streamcourse just after a right hand bend. It is then only a short distance down the canyon to the last rappel at 3230ft and a little over 5hr from the start. This is a 50ft vertical descent down a broad cliff. The anchor is a stout bush on the right. This is immediately followed by a 25ft drop that is readily downclimbed by means of the gully on the left. The canyon gradient then eases as the exit approaches. A little more boulder hopping brings you to the canyon exit at 2950ft. Here you will encounter a short dirt road that leads to an asphalt road behind some houses. Veer left and follow the asphalt road past the houses to the Green Mountain Ranch parking area where you left your return vehicle (34o14.03'N 117o29.63'W, elevation 2840ft). The 1.8mi descent from the radio towers should take about 6hrs. A pleasant tavern at the Green Mountain Ranch serves welcome refreshment.

Last updated 1/12/03.
Christopher E. Brennen