This is a family photo album from the 1930s and the museum uses it as an example of how people were manipulated by the Nazi regime. The text here talks about “the creator of Greater Germany” and the photo is of a “triumphal drive through old Cologne”. I don’t know if the creator of the album survived the Second World War, but I wonder whether they thought it was all such a good idea with millions dead, German’s size reduced by 25% and Cologne left in ruins.
This particular visit appears to be from when Hitler visited Cologne on 30 March 1938. He toured the city in his car and then gave a speech to 60,000 people at the Cologne Exhibition Hall. The museum doesn’t give more information about the album but it appears to be on loan from the city’s NS-Documentation Centre.