North of Zurich, in the quiet countryside between the airport and the Rhine, the Töss river runs its last few kilometres through a wooded valley before joining the big river at Tössegg. Around Freienstein and Rorbas the valley is narrow and steep-sided, with mixed forest of beech and spruce, and the ruins of Freienstein Castle sit on a wooded spur above the village. It is a surprisingly wild corner for a place so close to Switzerland's largest city, and it is where many Zurich riders go for a short afternoon loop.
To the west rises the Irchel, a long, wooded ridge with walking trails and a tower on top, and the roads that cross it and run along its flanks are small, twisty and fun, through forest and farmland with views across to the Black Forest on a clear day. The villages here, Freienstein, Rorbas, Teufen and Berg am Irchel, are farming communities with half-timbered houses, orchards and vineyards on the sunny slopes. The Zürcher Weinland, the wine country of the canton, begins just to the north.
The riding is gentle and varied, with plenty of curves and short climbs, but the roads are narrow and you share them with tractors, cyclists and walkers, especially on weekends. The Swiss speed limits are strictly enforced, and the fines are high, so keep an eye on the speedometer. The Töss itself is popular for swimming in summer, with pools and gravel banks along the river, and the confluence with the Rhine at Tössegg has a small ferry and a restaurant where boats on the Rhine stop.
Embrach, about six kilometres away, is the nearest town of any size, with fuel, shops and restaurants. Bülach, a little further west, is larger and well stocked, and Winterthur, to the east, is a big city with plenty of culture and good museums. If you have time, ride north to the Rhine and follow it to the Rhine Falls near Schaffhausen, the largest waterfall in Europe by volume, which is about twenty kilometres away and makes a spectacular stop on the Grand Tour.