In reply to Mark Torrance:
Some ideas/info (swiss resident):
To get into the mountains, cable cars and buses as well as trains are useful, www.sbb.ch will give the bus links as well, if not cable cars. To hire a taxi to get from a train station up to a trailhead can be a good option as well.
For a short weekend, maybe somewhere a bit closer to Zürich than Engelberg would be better. The area on the north side of the Walensee (south east from the Zurichsee) under the sheer faces of the Churfirsten peaks is quite spectacular and has some options, here from my experience (but done as hikes, not running):
-Walensee north shore traverse Weesen-Walenstadt (or the other way), 5-6hr hike, ca.700m ascent or more depending on route (not always by the lake shore!), straightforward for running, mostly good paths.
-Shortish circular hike around Walenstadtburg (bus from Walenstadt), above north east end of lake
-Long hike over Hinderugg from Walenstadtburg, descent on other side or return over Nideri (col further east) but potentially excessive descent to the valley from Lüsis (1900m descent in the day, 1500 ascent).
For quick access to high ground the following spring to mind in the Glarner Alpen, south of the Walensee (but not much closer than Engelberg now):
-Area around the Stausee Garichti, "Mettmenalp": train to Schwanden, bus up to "Kies (Niederental)" (written "Chis" on the map you linked), cable car up to Mettmenalp pt.1608.
-Area above Braunwald: train to Linthal, funicular to Braunwald, chair lifts to Gumen pt.1901 at the foot of the Eggstock, some mountain huts in the area to stay at.
You should not be short of options, I guess it depends a bit how rough you want the running to be.
Richard