There is a description of the North loop in Wert's Bakeries #84. Here is a description of the loop (clockwise), credited to the Seattle Bicycle Club:
Starting Point: Gas Works Park. The North Lake Washington Loop is 42.3 miles. By adding to it, the Mercer Island Loop, you extend your overall ride by 9.0 miles. | 0.0 | R | Burke-Gilman Trail | | 7.2 | | Mathews Beach (Restrooms) | | 13.3 | R | 68th Ave NE (Very Hilly Route) | | | | For less hills and a 1.0 mile savings, continue and turn right on 96th Ave NE (Waynita Way) @ Wayne Golf Course Club House, mile post 14.0. Road continues as 100th Ave NE which becomes 98th Ave NE. (See also the Juanita Hill Bypass as an alternative)
| | 14.9 | | Continues as Juanita Drive | | 19.2 | R | 98th Ave NE | | | | Continues as Market Street | | | L | Central Way | | 21.3 | R | Lake Street | | | | Marina Park on Right, Kirkland Bakery on Left. | | | | Continues as Lake Washington Blvd. (Lakeview Drive) | | 24.0 | BL | NE Northrup Way | | | R | 108th Ave SE to 110th Ave SE to 112th Ave SE | | | | (Route follows along west side of I-405 going South) | | 26.0 | L | 114th Ave SE (Turn just after crossing NE 8th Street) | | | | Continues as Lake Washington Blvd. SE | | | | Continues as 118th Ave SE | | 29.0 | R | Lake to Lake Trail - Under I-90 Bridge (Wooden Bridge) | | 30.5 | | Entrance to Mercer Island Bridge | | 30.7 | | FOLLOW I-90 BIKE TRAIL ACROSS MERCER ISLAND. | | 33.0 | | Baseball Park Restrooms and Water Stop. | | 35.3 | R | Exit trail after last bridge to Lk Wash Blvd (at S. Irving St.) | | 36.4 | L | Onto Lakeside Ave (LK Wash Blvd) at North Leschi Center | | 37.7 | BL | Follow Lake Wash Blvd up hill through Lakeview Park. | | 38.5 | | Cross E. Madison (FOLLOW SIGNS TO ARBORETUM.) | | 39.6 | | Exit Arboretum | | 40.0 | R | 24th Ave E (across 520) | | 40.2 | L | E. Shelby Street | | 40.3 | R | Montlake Blvd. E (Across Draw Bridge) | | 40.5 | L | Across NE Pacific Street to UW | | 40.7 | L | Burke-Gilman Trail. | | 42.3 | | Finish at Gas Works Park | |
