I really like historical anniversary events, lots of pageantry and reenactments, and usually good information about the people who were there in the first place.
The Battle of Fort Harrison that took place in western Indiana Territory will be celebrated on Sunday, September 2nd. If you're in the area and enjoy that sort of thing, you might plan to attend.
[If you are an Indy resident, I'll bet you didn't even know there was another Fort Harrison. Since our Fort didn't start until 1910, the Vigo County one predated it by just a wee bit!]