Was the first enclosed U.S. ballpark Union Grounds, built in 1862?

The assertion that Union Grounds was the first enclosed U.S. ballpark built in 1862 is indeed accurate. Union Grounds, located in Brooklyn, New York, is widely recognized as one of the earliest examples of an enclosed ballpark, which marked a significant shift in how baseball games were organized and attended. The construction of such a facility allowed teams to have greater control over the game environment, including ticketing, spectator comfort, and the overall atmosphere.

Other ballparks followed, but Union Grounds is historically noted for being enclosed and paved the way for the development of more modern stadiums that prioritize fan experience and operational management. This characteristic of being an enclosed space that is specifically designed for baseball distinguished it from earlier venues that lacked such features.