The first section of Colonial Hills was platted in the 1920's. The first section of Colonial Hills was built in the 1940s.
Colonial Hills was not in the Village of Worthington when it was platted or built, it was in an unincorporated area. Colonial Hills was built as a rental community for executives at a defense plant near the Columbus Airport.
The Worthington Historical Society's Neighborhoods says the neighborhood was built in 1927 to 1941 by "WWII Defense Homes Corp" I think it was Defense Homes Corporation and they were built during WWII. Defense Homes Corporation became part of FHA in the 1940s.
The plat maps and a lot of what I know about the history of Colonial Hills is from the entry about Colonial Hills on Wikipedia written by George Campbell a Worthington / Columbus historian which says "Colonial Hills was built in an assembly line fashion that predated Levittown by five years." I knew there was a defense plant and that was why the houses were built but I did not know a lot of the details prior to reading the history on Wikipedia. 
There were nine styles of homes that were built "prefab" elseswhere and delivered to Central Ohio. The 1941 Plat was built first.
Colonial Hills had alleys when it was platted and built. The alleys in Colonial Hills were vacated, divided and deeded to the homeowners at some point. The homes in Colonial Hills were sold after the Second World War, many to investors so many homes remained rental property for many more years.
Today Colonial Hills is a thriving Worthington Ohio neighborhood.
Image credit both images, 1927 Plat and 1941 Plat are from George C. Campbell and according to Wikipedia are in the public domain. "This work has been released into the public domain by the copyright holder. This applies worldwide."
