Cox Lake
Cox Lake is located just a little over 6 miles from the city of Spearfish. It is an interesting lake and has what is described as a sinkhole that plunges to a depth of 65 feet near the dock. There is a steady artesian water flow within the lake, and it is a popular fishing spot for the locals. If you want to see the sinkhole look on Google Maps in the satellite image and zoom in. Interesting note - this lake is similar to the lake at the Mammoth Site in Hot Springs, South Dakota that trapped mammoths thousands of years ago. The lake rarely if ever freezes over in the wintertime.