Oskar Blues Old Man Winter Bike Rally. An Epic Winter Adventure By Bike. Take on this 50km or 100km bike rally filled with DIRT, SWEAT, SNOW, and BEER in the world-famous cycling mecca of Boulder County, ColoRADo-from Lyons to Boulder and beyond. 50km ?Short Course? - laid back rural gravel and paved roads with beautiful mountain views 100km ?Long Course? - Competitive Rally with a mix of trail, gravel, and pavement and almost 5000ft of climbing Celebrate after at Oskar Blues Brewery with hot food, cold beer, and live music.