Here are some photos from Griffith Observatory and the hike up there. The observatory isn't just a place to see a view of downtown Los Angeles or the Hollywood sign, but there are also various exhibits, for example a Tesla coil and a Foucault pendulum
It was very dark and a bit foggy so the photos could have definitely been better with proper conditions.
The observatory was a pretty cool place but it was really just a way to kill time before the next morning when we would go to the Universal Studios. I expected the Universal Studios to be the highlight of the entire vacation, and it was more fun and more exciting that I ever could have hoped.