Now that the pandemic restrictions are easing, if you ever visit the San Francisco Bay Area, I highly recommend you take the ferry from Pier 33 and head out to the infamous Alcatraz. It's a very short ride. I was joined by my sister and brother in law from Ohio when they vacationed here and we went on the walking tour through the prison. The award winning narration and sound effects you hear through the rented headset are really outstanding. The audio tour is optional, but you'll be missing a lot if you decline. You'll get an amazing look and listen into the way things used to be for the inmates and guards. It's a bit creepy, but fun. Bring your best warm jacket or a coat! It can be chilly out there, even in the Summer. Or as Mark Twain said, "The coldest Winter I ever spent was a Summer in San Francisco."
Travel tip: Get your tickets in advance as the tours book very quickly. Showing up at Pier 33 the day you want to go over to Alcatraz is no guarantee of being able to go that day. You can get ticket information here
Bonus travel tip: There are 2 bathrooms on the ferry and only a few on the island. It's a good idea to check with the island personnel when you get off the ferry as to where they're located. (Take it from a guy who had an "emergency close call" shortly after arriving on the island).