I am thinking along the Sihl - then up to the ridge - back to Uetliberg - Uitikon - then back to Zurich. Should have no problems with the time element.

Pace won't be anything brutal.

I can confirm the route:

Paradeplatz - Sihltal - Uetliberg tunnel - Upto the ridge - along to the tower - up the tower - along the ridge - down to Hohenstein - along the mid level Friesenberg ridge - down to the Sihl (at the running track) - Paradeplatz.

Approx 19km - climbing from 420m to 900m (Top of tower) - main climb = 480-780m in 3km (5.9-8.9km).

Change your run Assasin - and come out in the evening!!

We were out for 1:55 + a short break at the top of the tower.

Lovely run - great conditions.