Ideas for this Summer's Chicago Area Drives

I wanted to have a post that we could all share our ideas for future Chicago area drives. From my perspective there are two distinctly different ideas; (1) day trips that are easy to reach from Chicago or it's suburbs and (2) trips that require a stay overnight in a hotel or B&B.

Several people have recently mentioned the latter with some great ideas. Obviously the downside is that it would greatly limit the amount of people that could attend due to time contraints etc. The upside is that it would most likely be a great time and a nice mini (no pun intended) weekend getaway.

While I'm not against that idea I think we may want to focus the majority of our attention on events that most of us can make time for. Chicago folks, what are your thoughts on this?