OK, I've never done this hike before. It's supposed to be hard, with lots of use of your hands on the way up and down, and with slippery sections, Bring poles if you got em. The maps show trails there, and the elevation gain goes from 800 to 2800 feet in 4 miles or so. We're going to take our time, but read the description below--this hike is hard!
LENGTH: AT LEAST 8, MAYBE 10 MILES, 10 am to 4 pm, followed by massive caloric intake somewhere nearby afterward
DIFFICULTY: DIFFICULT, EXPECT TO SWEAT, COMPLAIN, AND THEN SAY WOW, WHAT A COOL HIKE!
FREEWAY DIRECTIONS: 101 freeway west to Thousand Oaks, take Wendy Drive offramp to (left) south and park where Wendy makes "T" with Potrero Road.
MAP LINK: "A" IS WHERE TO PARK, "B" IS TRI-PEAKS:
PRINTABLE TRAIL AND TOPO MAP: http://photos2.meetupstatic.com/photos/event/1/a/6/0/highres_136086752.jpeg
EVEN MORE DETAILED TRAIL AND TOPO MAP:
THE USUAL STUFF:
BRING ALL THE USUAL STUFF, I'M NOT YOUR MOM....
Bring lunch, clothing (sorry, nude hikes are a different Meetup group), lots of water--4 liters, hat, comfy shoes, snacks, all your troubles..., camera, etc
LEGAL STUFF: by going on this hike, you agree to assume all risks of this hike, and that no one at Meetup including the organizer is responsible for your safety. See the Meetup terms of service especially paragraph 6.2:
You can see my blog at http://rare-earth-news.blogspot.com (http://rare-earth-news.blogspot.com/) for stories on new parkland purchases and other environmental battles, like the recent addition to Vasquez Rocks park.
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Here is a description of the hike up and down from http://www.venturacountytrails.org/TrailMaps/Sycamore/AreaTrails.htm# (http://www.venturacountytrails.org/TrailMaps/Sycamore/AreaTrails.htm)
 Western Ridge Trail to Boney Summit
Description: The Western Ridge Trail is the most spectacular (http://www.venturacountytrails.org/TrailPhotos/BoneySummitLoop/_Page.html) way to get to the Boney Summit, but it provides some hiking challenges. The trail starts about 1/2 mile from the north end of Old Boney Trail, near the highest point where the trail turns right, the Western Ridge Trail starts off to the left side and heads up the ridge. The trailhead is somewhat hidden, next to a more prominent spur that heads down to the left, but ends in a few dozen feet. But once on the trail the way is quite obvious. Even though it is well-travelled, it is quite narrow through the chaparral so best to be avoided during tick season. There are also many very steep sections, some that require a small amount of rock climbing. There is one narrow section about 2/3 of the way up with a rock cliff on the right that has some poison oak in the chaparral on the left, but it can be avoided if you keep a good watch for it.
This is a tough hike but the incredible views and the satisfaction of overcoming the challenges make it all worthwhile! Nevertheless, it is better to take an easier route to the summit the first time. The Upper Cabin Trail is a little easier but almost as steep and looser in places. The easiest route to the summit is from Circle X Ranch (http://www.venturacountytrails.org/TrailMaps/Backbone-YerbaBuena/AreaTrails.htm), via the Tripeaks Trail (http://www.venturacountytrails.org/TrailMaps/Sycamore/AreaTrails.htm#TripeaksTrail).
Once on the trail, it is quite easy to follow for most of it. However, there are some places where it's easy to go astray, so you can download a GPS track (http://www.venturacountytrails.org/TrailMaps/Sycamore/Tracks/WesternRidgeTrail.gpx) to help you along.
Usually we take this trail up to the Boney Summit and then go back down on the Upper Cabin Trail.
 Upper Cabin Trail to Boney Summit
Description: The Upper Cabin Trail starts at the old cabin site and climbs to Boney Summit. It is a challenging trail, steep and very rocky and rutted in many sections, and sometimes loose as well. But the view from Boney Summit and points along the way make the hike worthwhile. The trail is very well travelled and so overgrowth generally isn't a problem. There is a photo gallery (http://www.venturacountytrails.org/TrailPhotos/BoneySummitLoop/_Page0003.html) dedicated in part to this trail
To help you to find your way, you can download a GPS track (http://www.venturacountytrails.org/TrailMaps/Sycamore/Tracks/UpperCabinTrail.gpx) of the Upper Cabin Trail.