[4] Romdahl became leader of the governing body of the Handicraft Union's school in 1909, of the committee for the Charles Felix Lindberg Donation Fund, and of the Röhsska Museum.
[5] Romdahl's many friends and contacts included Leonard Jägerskiöld, Erland Nordenskiöld, and Albert Ulrik Bååth and he seems to have liked Gothenburg.
Even when Romdahl arrived in Gothenburg there was a great lack of space in the East India Company building at Stora Hamnkanalen.
After years of discussions, the new museum at Götaplatsen was built; it served as the main entrance to the Gothenburg Exhibition and then grew to become the city's cultural centre.
His life's work is symbolised by the art museum and Linköping Cathedral; in 1911-16 he and Sigurd Curman conducted building historical studies there.