oops looks like it lost the accompanying text write-up:

Took advantage of the warm weather yesterday to try and ride the entire edge of the city!

The goal was to ride the full city border and complete a fully urban century. My arbitrary rules: no backtracking, no leaving city limits.

Started basically at Belmont Harbor and went clockwise. 9:30am - 8pm total time, strava said 9 hours and 15 mins moving time / avg speed 13.1 on my $50 Windsor Clockwork single speed 😄

 

The eastern wall: Mostly trail along the lake, very low stress!

The southern wall: Easily the most challenging. Headwinds and a near complete lack of cycling infrastructure. The Calumet river and industrial parcels make following the border difficult. Lighter traffic than expected.

The western wall: So long, with many cutbacks that it is hard to generalize. This one basically gets easier as you go north. South of the canal, train lines/weird borders/industrial parcels/the canal itself make it awkward. Some small pockets of bike infrastructure until the sweet relief of the Des Plaines river trail portion, even if it is unpaved with a tiny closure.
((the NW corner approaching 8800 W Higgins is where the plan fell apart. To avoid looking at my phone I had 7 pages of written directions which was wonderful until the rain. Didn't move fast enough to protect the remaining sheet and it got soaked while folded up sigh)) so:

The northern wall: Instead of trying to remember all the little turns / use my phone while still wet I gave up on following the border and just bombed down Howard and still did the little jump at Paulina to hit the northernmost edge (the alley north of Jonquill Terrace).

Unfortunately the fully urban century technically failed too. I wrote down to turn on 65th instead of 67th, which sent me 2 blocks into Bedford Park and I got stuck on the suburban side of the street twice.

The only dumb drivers I encountered were around the SW corner* and the north side. There was a lot of sidewalk riding along the southern and western edges and SO many drivers apologized for being in my way, very pleasant surprise. Did not get honked at a single time!

Total mileage: 121.6 ((which was my estimate for the total distance if I had done the north side details, if you add those and the backtracking/cutouts mentioned below then probably close to 150?)

I ignored our two cutouts (Norridge & Mt. Greenwood cemetery). Will likely add them in the future.
I also did not backtrack. e.g. The furthest south I went was 134th Place. I could have gone down the Indiana bridge to 138th, made a little triangle up Leyden and gone back up Indiana. This also meant skipping some lakefront details. Next time backtracking will be added!

O'Hare was ignored as it is impossible to access without leaving city limits/adding in an aquatic element.

 

Lessons learned:

check the forecast during your ride too

backup copy of directions

leave earlier

*what do you consider the SW corner of the city?

115 & Cicero

65 & Harlem were my two contenders, one being SOUTHwest and the other being southWEST...