The lands you've discovered are part of the Cross Plains Unit of the Ice Age National Scientific Reserve. For now, there are a few unsigned trails on both sides of Old Sauk Pass, but no other development. However, there are plans to develop this area further as part of what the National Park Service calls the "Ice Age Complex at Cross Plains". You can read more on the NPS website (http://www.nps.gov/iatr/parkmgmt/crossplainsgmp.htm
). This area will one day host a segment of the Ice Age Trail.
The lands south of Old Sauk Pass (where there's a kiosk/info board, locked gate and an old farmstead) are owned by the National Park Service. There's a nice mowed path for hiking you can access by hiking up the driveway past the house and barn.
The lands north of Old Sauk Pass are owned by the DNR. Numerous trails course through this area but there is no signage to guide hikers...explore as you go. The highlight of this area is Wilkie Gorge, which you can find by crossing Old Sauk Pass and angling northeast if you park at the NPS kiosk.
The area north of Old Sauk Pass is technically "Cross Plains State Park", and though it's owned by the DNR it's pretty much unique among state parks in that it's completely undeveloped.
As to why it says "Ice Age Trail Alliance" on Google Maps south of Old Sauk Pass, I believe that's an unfortunate by-product of Google's public-access system for naming things on their map. The Ice Age Trail Alliance is a non-profit organization that helps build, maintain and promote the Ice Age Trail, and although we are a land trust that owns some land along the Trail's thousand-mile route, someone has gone through the state suggesting that Google label areas "Ice Age Trail Alliance" that are not owned or managed by the IATA. I've pointed this out to Google but evidently it's easier to get things put up than to have them taken down.
In any case...although the area you've discovered is undeveloped and mysterious at best (unwelcoming at worst), I'd highly recommend going for a hike here if you enjoy poking around quiet areas that not many people know about.
Call us (798-4453) or email us (info at iceagetrail.org) at the IATA if you'd like info on hiking established segments of the Ice Age Trail, or stop by our business offices on Main Street in Cross Plains.
Eric, IATA Staff