I'm sure everyone has their favorite annual events around the state, but for me the two stand-outs are "My Place" and "SWORFI".
The first event on the calendar takes place on Sunday Oct 1st. It is the South West Ohio Regional Fly In (SWORFI). This fly-in is held at Winemiller farm near Blanchester, on the East side of Cincinnati. Todd Winemiller puts on a great fly-in with many interesting aircraft and great food. The field is 2,700 ft long and extremely smooth.
The airfield is not depicted on the sectional, but you will find it at coordinates N39°12.52' W84°0.75' or N39.207667, W84.019361 (Different GPS use different formats). You can also see it on Google maps here. Todd operates his North American T6 out of the field so it will certainly accommodate most light aircraft. The EAA chapter awards prizes for all kinds of categories.
Last year I saw several aircraft I had not seen before and generally had a great time.
The second fly-in coming up is Joe and Lynn's "My Place" fly-in. This one takes place the following weekend: Sunday Oct 8th. Joe and Lynn put on a fantastic event with wonderful food, arts and crafts, a get-together around the farm pond, young Eagles flights, several helicopters and lots, lots more.
The airport details can be found here: http://www.airnav.com/airport/3OH7 The runway is about 2,000 ft by 40 and now that the barn and power lines have been relocated (thank you Joe) the approach is clear.
Hope see everyone at both events :)