You can do about a 30-minute hike from the parking lot below to the Griffith Observatory on top of the hill (or you can just drive all the way up there). There’s a good view of Los Angeles during the day and a planetarium show at night.
From the Hollywood Freeway, drive north on Western until it goes right. Then turn left on Fern Dell and park and hike (or drive) to the top.
Or take the Red Line subway north to Sunset/Vermont then take the LADOT bus to the Observatory.
