You might be thinking of the FIRST World’s Fair in Chicago: The Columbian Exposition in 1893. That was the White City. Only one of the main buildings deviated from the plan (because the architect in question was ticked off at the Fair’s architect).
A number of the homes of the future from this World’s Fair were ferried over to Beverly Shores, Indiana in the Indiana Dunes National Lakeshore. There are very occasional inside tours – I think possibly only once a year – but you can walk by them any time.
