Biking around Lake Michigan, Emanuel rode more than 900 miles and through four states.
"Completing a long held dream, I just finished circling the entire Lake on a bicycle," Emanuel wrote on Facebook Tuesday.
From "awesome" sunsets on one side, to "breathtaking: sunrises on the other, Emanuel said he rode from the new Chicago bike trail to the old rail lines of Indiana.
"The true character of the Lake is reflected in the people around it. Everywhere I went, people were quick with a hello, easy with a smile, and generous with their help. It is a Great Lake surrounded by great people in a great country," he wrote.
Emanuel and his friend from their time in the Clinton White House completed the journey together.
Emanuel left his public office as Chicago's 55th mayor last month and has since signed a deal with ABC News to serve as an on-air contributor, sources say.