Absolutely weird.  That is how I would desribe Pine Hills Nature Preserve.  Located in West/Central Indiana bordering Shades State Park, the preserve contains terrain and geological formations that are not found anywhere else in Indiana or the surrounding area.  The preserve features "backbones" or very narrow rock ridges that seemly come from no where.  As you enter PHNP, things look like a typical hike found in Shades or the neighboring Turkey Run SP.  Very quickly though the Earth around you falls away and you are left on a ridge with a beautiful if not dizzying view of a large meadering creek well below you.  A stair case takes you off of the ridge down to the creek where you can choose to go either left or right.  One of the highlights of the hike is when you cross over the Devil's Backbone; a six foot wide ridge with a hundred plus foot dropoff on each side.  Definitely not recommended for those affraid of heights.  The Honeycomb wall is also something that you must see as it is very strange; it is a large rock wall that looks just like what it is named after, a honeycomb.  Also one of the greatest things about this place is its seclusion.  When we were there, we only saw a couple people in the preserve along with Shades SP.  This does make it a little creepy if you read some scary legends about this place before hand though. 

You can access Pine Hills directly by highway IND 234, but I prefer going to Shades SP and parking the northern parking lot where trails 1,6, and 9 start.  This way there is only a short hike to trail 10 which will lead you to the preserve as well as then you can go hiking in Shades once you return.  In all, I have hiked many trails in Indiana and this is by far one of the best.