I went to the Monterey Aquarium two summers ago with my girlfriend who was living in San Fran for the summer. She could not understand why I did not want to see the sights in San Fran and why I wanted to see some fish and a huge glass wall down in Monterey. She ended up enjoying the experience and I got her some Jelly-bellies on Cannery Row, so she was happy.
Drive down scenic Castro Street.
It's like touring a sewer in a glass bottomed boat...