Springfield's state
Wikisimpsons - The Simpsons Wiki
Springfield's State is a matter of much debate among fans. Popular theories have been Illinois, Maine, New Jersey, Texas, Missouri and California. However, it is unlikely that Springfield exists in any real state, because of all the conflicting evidence which has been given. The "fictional state" theory has been further evidenced by a trailer for the upcoming movie in which the four states which border Springfield are stated to be Ohio, Nevada, Kentucky and Maine, which never come to a junction in the real world.