The Potrero Ridge Trail in Newbury Park is an interesting ridgeline trail that runs west/east in three sections over about 2 1/2 miles one way. You can access the trail from a number of locations and neighborhood feeder trails, but the main sections are as follows (west to east):
Via Las Brisas in the Dos Vientos tract, just north of Paseo Santa Rosa to Reino Road, just north of Paseo de Leon and Lynn Road is a little over a mile and one of my favorite trails providing panoramic views of the southern portion of Newbury Park, Boney Mountain and Dos Vientos. There are some switchbacks on the west end near Reino Road but they are not overly strenuous.
The middle section of Potrero Ridge Trail runs from Woodland Oak Place off of Reino Road to Wendy Drive between Felton and Peppermint There's where there's a convenient dirt parking lot. Only about a half mile to the top of the trail, where you'll see a water tank and above there a section that treats you to wonderful, panoramic views of the area.
The east section of the trail runs from across the parking lot on Wendy Drive to another peak, then down towards Silas Lane near Grace Bible Church, about half a mile in total. There is no parking available for this section of trail, though you can park in the Wendy lot and find a crosswalk to cross over to the trailhead.
So basically these 3 segments are split between Via las Brisas and Reino Road, Reino Road and Wendy Drive and Wendy Drive and Silas Lane.
This trail is maintained by the Conejo Open Space Foundation.