The Griffith Observatory is one of those things in LA that you have to do. Whether you just want to check out the observatory yourself and get a pretty good look out at the expanse of city limits, or you want to do your best James Dean impression, the building has a lot of history and is a stunning structure on its own.
If you’re feeling a bit more motivated I’d highly recommend the hike as well. It’s dog friendly and you get an even better view of LA and an up close and personal view of the Hollywood sign for a truly LA experience.
One of the last times we did the hike we saw Nick Kroll and Jason Mantzoukas from the League out enjoying the trail and I’ve seen a handful of other celebrities posting from the hike, so your chance of checking off a celebrity sighting while on the hike is also possible.
Bring some water, and poop bags if you have a pet and good luck with parking. Wish I had some advice there but it’s always a crap shoot for me.