Dignitaries including Prime Minister Maris Kucinskis and Riga mayor Nils Usakovs attended a re-opening ceremony after which the doors were thrown open and the public flooded the exhibition halls.
Reaction to the three-year facelift was overwhelmingly positive.
The renovation has doubled the total exhibit space, so visitors will either have to be patient or explore the museum over the course of several visits.
A mobile app featuring descriptions and an audio guide about each of the paintings will inform people about what they're seeing