Today I walked to the gym, a half-hour trek that usually takes me through Horner Park. The day was in the 80s (still is as I write this), sunny and gorgeous, with a perfect light breeze. At the north end of the park is a modest hill, the epitomization of grassy knoll (sans assassins). This being Chicago, it is certainly unnatural, and looking at the wide even banks of the Chicago River which abuts the park on the east, my guess is it was created as a byproduct of dredging and reshaping that stretch of waterway.