My city is small but is nestled between several large cities so there are a few festivals that are cool.
NJ festival of ballooning is in south jersey but it isn't too far and it is pretty cool.
Hoboken has an Italian festival, an Irish festival, and an art and music festival.
In Jersey City there is a large Indian population. Their Diwali
festival is pretty cool. I can't find any pictures but the whole Indian section of the city get a very colorful makeover. You can buy Indian food and listen to Indian music and dance. Thousands of people dancing in the street late at night is pretty cool. According to my ex it is also a great place to pick up girls since the abortion rates spike right afterward.