 So you're talking 2,000 show up at the rendezvous and they've got 10,000 horses. You need a lot of grass. Early rendezvous were short. Over the years, the time extended to about a month. By the 1840s, the beaver worldwide had dwindled. Prices were too high for most to afford hats, and alternatives such as silk became the standard for top hats. Soon, wagon trains of pioneers headed west would begin to cross this area. But the days of the mountain man rendezvous were important to the time period and an event that has recreated in some fashion in many locations of the American West.