Right by my apartment, I can't help but come here often. It's situated right around the historic La Brea Tar Pits. One needs to spend an entire day here. Also love their magazine/book store.
The Rose Bowl happens in Pasadena. The Flea Market is only once a month, its usually the second Sunday of the month. Its a great place to find vintage clothes, antiques and rare treasures. I once found an amazing David Hamilton book that I bought for $15 when it was worth $500.
I love living in a city where I can easily go hiking during the day and be home by dark. Griffith is just massive and untamed, it has a wild feel about it in places. Views of LA, the ocean, and the Hollywood sign.