Rancho Sierra Vista of the Santa Monica Mountains National Recreation Area in Newbury Park is probably my favorite place to hike in the Conejo Valley. Though it suffered from fire in 2013, the variety of trails and views are what set it apart. From the main trailhead, you can select from any range of trails for what length you are willing to go for the day. This ranges from a short loop around the large meadow, deep up in the Boney Peak area, or towards the ocean through Sycamore Canyon Trail.