How much time should I allocate to visit the Klein Matterhorn Glacier Paradise from Zermat?
Depends on what you want to do! Some people go up and stay all day to ski, hike, or climb. When we went we spent about two hours. We first had lunch next to a big window with great views. Then we went up to the observation deck to enjoy the view of the top of the world. If you just want to see the views you can easily ride the gondolas up, spend 45 minutes looking around, and then come back down.
This particular gondola ride is one of the most breathtaking in Europe IMHO...entirely worth the price, which is not cheap!