I visited Big Marsh Bike Park with a friend three weekends ago to ride mountain bikes on the single track, check out the park’s campsite, see if people were still drag racing on Stony Island Avenue (they were), and finally, try to get a sense of where the access trail from Pullman in the west will cross over Lake Calumet by viewing the “land bridge” from the air.

According to the “preferred alignment” map below, the future bike trail will cross the lake at the shortest opening where the spit is on the left. The photo is facing due west.

While researching the proposed multi-use trail, boardwalk, and bridge, I decided to look up historic aerial photos to try and understand when and where the land around the lake was filled in. (I think the Illinois International Port District is the proposer.)

The Lake Calumet diptych I made shows two aerial photos – taken from airplanes – of Lake Calumet in 1970 and 1995. The images come from the Chicago Metropolitan Agency for Planning’s collection of three decades of 6,300 aerial photos across the six country region.

In the 1995 image you can see the Harborside International Golf Center built on landfill (also in 1995), additional slips for ships, and other land and water feature additions and subtractions.

The two photographs were taken slightly offset from each other but I scaled and adjusted their alignments to match each other as best as I could.