On the Lincolnwood side of the street was a forested strip of land, or maybe more of a wasteland, which was part of the Chicago Reclamation District (CRD.) It ran parallel to the North Branch of the Chicago River which was on the west side of the strip and maybe 100 yards away from the street. At the time was called "The Canal."
During the summer the canal smelled kind of rank. We always assumed that it was a sewage canal. In reality it was just that the slow moving water became putrid during the dry summer and thus the foul smell. Now-a-days it is called "The Channel" because that sounds better then "The Canal" and since the Chicago River has been cleaned up, the canal no longer smells.
Venice is made up of canals (which also happen to smell bad during the high summer months) so I am not sure why the fuss and name change.
The forested part which ran the length of our block, was a place to play with neighborhood friends. It was magical and like being in the Indian wilderness. We played hide and seek, found tennis balls by the dozens (for some reason not quite clear to me,) and dared not to go too close to the canal under penalty of punishment by our parents.
Deep into the area, not visible from the street because of the forest (forest to a child, overgrowth to an adult) there was a cabin/shack/office (call it what you will) on wheels. It looked much like the picture below which triggered this memory. It was in horrible condition, rusty, and dirty.
The lock on the door had been broken and we used to sneak, with great glee, inside to investigate. I believe now, in looking back, that it must have belonged to the CRD because it has old receipts, forms, broken pencils, binders with information, etc all worn, dirty, and falling apart with age.
Along the side with the window, boarded up, was a wooden desk, rough and splintered where most of the supplies were kept. There was a metal stool with a high back. It was so dirty that we didn't dare sit on it or touch anything.
There was always the air of "getting caught" which made our visits more exiting. Every now and then there was evidence of others having visited the "office" and we liked to assume that it was the "authorities!" Most likely the visits were from other kids like us.
To this day I can take the memory no further. I wish I could visit the place again with adult eyes, find out more about the who-when-why of the place, and photo document the experience. Meanwhile, this picture will have to suffice: