Main Street will close to vehicles at 2 p.m. Saturday and parking at China Bridge will be a flat-rate of $15 from 2 p.m. to 6 p.m.
City officials ask residents to walk, ride or take free transportation to Old Town. Leashed dogs are also allowed on city buses.
Local businesses will open their doors to trick-or-treaters starting at 3 p.m.
Main Street will reopen to vehicles around 6:30 p.m.