Mount Everest, perhaps K2.
Although the summit of Everest is at a higher altitude, K2 is a much more difficult and dangerous climb, due in part to its more inclement weather and comparatively greater height from base to peak.
Most likely, you would.
April, May and early June is the best time to climb Mount Everest before the monson arrives.
Nanga ParbatAnnapurnaK2Gasherbrum IVKanchenjungaDiran Peak (very few people know about it)DenaliMakaluMount KeaLhotseI wouldn't consider Mt. Everest to be a part of this list. It may be the highest but is not difficult.
1996
1996
Most expeditions take place on Mount Everest during March to late May because it is the safest time to climb the mountain. In early June the monsoon arrives bring very bad weather that makes it impossible to climb on Everest.
In North America, Mount Rainier is probably the most challenging mountain to climb. Joining an expedition to scale it should be good training for Mount Everest.
Most attempts to climb Mount Everest are made in the month of May before the monsoon season starts.
The main climbing season for Mount Everest is the end of April to the end of May.
The two main routes to climb Mount Everest are the South Col - South East Ridge from Nepal and the North Col - North East Ridge from Tibet.