If you are anywhere on the West Side, then there are several nice hikes in Topanga State Park that are very easy to get to. From where we live in Culver City, it take 20 minutes or less to get to any of the hikes listed below and it is even faster from UCLA or Santa Monica.
1) Paseo Miramar:
The 5.5 mile Paseo Miramar Hike in Topanga Park is a strenuous out and back hike with beautiful ocean views. The trailhead starts at the end of Paseo Miramar off of West Sunset Boulevard in Pacific Palisades and leads along the ridge with a turnoff to the Parker Mesa Overlook. (See the map below for the location of the trailhead.)
The Paseo Miramar Trail:
View over Los Angeles from the Paseo Miramar Trail:
2) Temescal Canyon Loop
This moderately strenuous 3.7 mile loop starts at the Temescal Gateway Park where there is parking for $7, bathrooms, water fountains, picnic tables, and maps. Follow the Temescal Canyon Trial up the shady canyon and then follow signs to loop back to the park on the Temescal Ridge Trail. This is a nice varied trail with ocean views, shady trees, and a little waterfall.
3) Inspiration Point Trail
There is an easy 3 mile loop from Will Rogers State Park that goes up to the lookout at Inspiration Point. At the park, there is parking for $7, bathrooms, and water. You can also tour Will Rogers' old ranch.
I got the ideas for these hikes from the book "60 Hikes within 60 Miles: Los Angeles including San Gabriel, Ventura, and Orange Counties" by Laura Randall.
Here is a map marking the Paseo Miramar Trailhead, Temescal Gateway State Park, and Will Rogers State Park:
View Paseo Miramar in a larger map