The North Shore Channel Trail was the first bike trail I ever rode in Chicago. While it’s not particularly long or interesting, it is pretty useful as a connector (and completely paved!). You may know it as the Skokie Sculpture Garden trail as it’s the trail that winds past all of the truly ugly sculptures north to Evanston.
The trail starts at Francisco and Lawrence and runs through the river front park until Peterson where you have to switch to the other side of the river via surface streets because no one has bothered to put in an underpass. The trail is fairly well used through this section, but primarily by pedestrians. It’s definitely got nothing on the Lakefront Path. On the north side of Devon, the trail branches into two paths connected paths which are a few yards apart from each other and continues as such north to Emerson. This definitely reduces trail congestion as there is no clear advantage over taking one path or the other.
The trail eventually ends at Green Bay Road, but I usually get off the trail at Bridge and use it to connect to The Green Bay Trail.