I really enjoyed the climbs near Death Valley, CA. From Stovepipe Wells at sealevel to Towne Pass at 5000ft then down to Panamint Valley at 1000ft then back up to 4000ft all within 40 miles on Hwy 190. Do that as an out and back 80 miler and I'd call it "epic."

Another option is the Tour of the California Alps, or "Death Ride." http://www.deathride.com/index.html