In August, the cities of Tohoku compete to put on the largest/brightest/loudest/weirdest festivals to attract visitors and ensure a bountiful rice harvest. Aomori specializes in giant lanterns depicting mythical characters that are pushed around on carts and floated on the sea.
If you are in Aomori with an hour to spare visit the festival museum. Here you can see prize winning floats from previous years. The workmanship is impressive and you will definitely want to return for the festival itself.