Alcopark parking garage is the big circular parking garage near the lake and main library in Chinatown. It's one of the three Alameda County parking garages (the others are Oakland Parking Facility at 587 7th St. and Amador Parking Facility at 24360 Amador St. in Hayward). It's $7 per day for the public and $6 per day if you have juror validation. It's 9 levels overall (2 are below ground) and has 700 spaces. The address is 165 13th Street.
The structure was built in 1962. The architects were Ratcliff, Slama, and Cadwallader, who also designed the Alameda County Administration Building next door.
It has a heliport on its top!
Does anyone know why this parking garage is circular?
Here are its yelp reviews (they include details on parking here).