Of course, it's awfully hard to pin it down to just three great ski tours. It leaves out among other things: ski and climbing trips to Kathadin, leading long multi-week outings for the Colorado Outward School in the Collegiate range; as well as wonderful days skiing gullies in Tuckermans Ravine, or multiple 160k Canadian Ski Marathons. But, the three gems I will share certainly stick out in my mind, for sure!
As previously mentioned my best ski tours were in Zermatt in the early 1990s, using the unheated winter room in the old hut on Theodul Pass as our base. The gear has changed quite a bit since then, as I was skiing with leather boots, (and the enclosed setup) cable bindings, on Karhu XCD skis. Nevertheless, I tagged the summit of Breithorn and Pollux (4000m) with Gary, Susie, and Ben, then skied the Schwarztor to the Monte Rosa hut; the next day Gary and I ascended the Dufourspitze, and skied the 10,000' vertical back to Zermatt.
It really doesn't get any better than that, however since I am in my 70s, I have to say for sheer TYPE 1 FUN, skinning up toward Findeln for 90 minutes, and then locking your AT gear in downhill mode, and stopping at the trail side Champagne Bar for sunset … is a sublime experience. Nor, does a late afternoon skin up to Furi, and making a stop at the Hennu stall on your way back to Zermatt; the atmosphere is a full on mega-party …you'll wish you were 40 years younger!