 Writer Ian Maxtone @-@ Graham , a former resident of New York , had conceived the idea of having the family travel to the city to locate their missing car and believed it to be " a classic Manhattan problem " . Bill Oakley , who had visited the World Trade Center when the construction of the towers was completed in 1973 , suggested parking the car in the plaza of the buildings . Josh Weinstein observed that , " When we realized that there was a plaza between the two towers , we knew it was a perfect spot to have Homer 's car . " 
