The Carnegie library building is now under the care of a new non-profit called the Carnegie Museum of Kings County.
A gift from the wealthy industrialist Andrew Carnegie, the building served as a library from 1905 to 1968.
Officials with the non-profit said they are focused on making improvements to the building, including seismic upgrades.
In the meantime, they have a mix of exhibits for the public to enjoy on-site and online.
"Check out our website at carnegiemuseumofkingscounty.org, and you'll see what exhibits we have. We're doing themed exhibits to try and get different audiences involved with the museum," said Jack Schwartz.
Friday's grand reopening was part of Hanford's 130th birthday celebration.