To get to Alcatraz you
When you arrive on The Rock you have the option for an audio tour or a guided tour (seasonally, I think?) There were no guided tours the day we went but I totally would have done it had their been. We did the audio tour and it was really really good. The tour is guided by former guards and inmates which is super interesting. Make sure if you are traveling in a group you start your tour at the exact same time
Seriously, the day could not have been better. It was a very happy birthday indeed!