There's no nonstop way to get from the Sonoran Desert to the Norwegian fjords, and that's precisely what makes routing strategy the whole game when booking business class from Tucson to Bergen. In practice, the smartest itineraries funnel through Amsterdam, Frankfurt, or Munich, then hop up to Bergen via Copenhagen or a direct KLM/Lufthansa feeder—total journey time runs close to 10 hours in the air, plus connection time. The factual anchor worth remembering: with SAS, Lufthansa, and KLM all serving segments of this corridor, your best long-haul business class experience will almost certainly come on the transatlantic leg out of a hub like Frankfurt or Amsterdam, since the Scandinavian short-hop up to Bergen is typically operated with a regional business cabin rather than a flagship product.
I've routed this trip through Frankfurt more than a dozen times, and Lufthansa's push toward the Allegris cabin—with its suite doors and adjustable privacy panels—has been rolling out on select 787 and A350 routes, so it's worth checking your specific aircraft type before booking, since older A340 business configurations still appear on some Frankfurt departures. KLM's World Business Class on their 787s and 777s out of Amsterdam remains a dependable, comfortable choice with lie-flat seats in a 2-3-2 or 2-2-2 layout depending on aircraft. My insider tip: build in a deliberate 3-4 hour layover in Amsterdam or Frankfurt rather than the tightest legal connection—both hubs have exceptional business lounges (KLM Crown Lounge, Lufthansa's Frankfurt lounges), and a relaxed connection means you land in Bergen rested enough to actually enjoy the fjords rather than sleepwalk through them.
Seasonally, May through September is when Bergen rewards the effort—long daylight hours, milder weather, and better award availability on the transatlantic legs as airlines add summer capacity into Northern Europe. Fares and premium inventory on this itinerary shift often given the multiple carrier combinations involved, so setting up fare alerts to track pricing fluctuations across SK, LH, and KL is the easiest way to catch a strong business class fare before it disappears.