This is the third in a series of 4 geocaches in the area, the last of which will be a mystery cache that you can only find if you find the first 3 and the final cache will only be accessible by kayak/canoe. Each of the first 3 caches has a number in the cap of the bison tube that you will need to find to get the coords for the finale.
This cache is located in Fox River Park, a great park in Silver Lake well known for it's expansive disc golf course as well as multiple different picnic areas.