Atlantic City, New Jersey
Marvin Gardens, the leading yellow property on the board shown, is actually a misspelling of the original location name, "Marven Gardens". The misspelling was said to have been introduced by Charles Todd and passed on when his home-made Monopoly board was copied by Charles Darrow and thence Parker Brothers. It was not until 1995 that Parker Brothers acknowledged this mistake and formally apologized to the residents of Marven Gardens for the misspelling although the spelling error was not corrected.

Q: What popular property in Monopoly was actually a misspelling?
Marvin Gardens