The route goes around the Lake Zurich (Zürichsee) & Obersee, 93km. The route is on roads and yellow trail. It's a loop, so you can start/finish anywhere, and go either direction.
Road: Zurich & Obersee, 93km, gpx "Lake-Zurich-Circum"
Road: Zurich only: ~67km around Lake Zurich only, which is entirely on roads. gpx "road zurich only"
Trail: Zurich & Obersee Path 84: The Variation "Path 84" is ca. 124km and adds significant vertical gain (https://www.schweizmobil.ch/de/wanderland/routen/route-084.html) gpx "zurichseenrundweg84)
Trail: Zurich only: ca. 100km, without Obersee. gpx "Route 84 Zurich"