The attraction, which features sets, props and memorabilia from the BBC series, closed in London in February to make way for its move to Cardiff Bay.
The new 3,000 sq m building is at Porth Teigr, next door to the BBC’s Roath Lock studios, where Doctor Who, Casualty and Pobol y Cwm are produced.
The exhibition is expected to attract up to 250,000 visitors a year.
The internal fitting of the building will take place over the coming weeks.
So, I know 99.9% of my followers aren’t anywhere near Cardiff, but on the off chance any of you ARE, you NEED to go see this exhibit. We went in London and it is fantastic. So many close-up photos of Whovian costumes eeeeeee! ^_^