How is it that union pacific is the largest railroad, even bigger than BNSF when they only operate in 23 states, and bnsf operates in 27 states, and that BNSF is owned by warren buffet, one of the largest men in the world?
Number of states served doesn't really matter. States vary greatly in size, and you only have to serve one town in a state to count it. Warren Buffet's ownership also doesn't matter. (If he'd bought Kansas City Southern instead, would that automatically make KCS the largest railroad? Of course not.)
From http://www.uprr.com/aboutup/corporate_i ... over.shtml and http://www.bnsf.com/media/bnsffacts.html:
Route Miles: UP 32,000 vs BNSF 32,000 (according to wikipedia, as of Dec '08 it's UP 32,012 vs BNSF 32,166)
Employees: UP 45,000 vs BNSF 40,000
Locomotives: UP 8,400 vs BNSF 6,700
Neither appears to be claiming to be the largest anymore, just saying "one of," but UP had more route miles than BNSF after acquiring Southern Pacific in 1996, and did claim the title for years. Now they are virtually equal, but UP still has more locomotives and employees. Route miles also include trackage rights; if you count only route miles they actually own (according to wikipedia) it's UP 26,171 vs BNSF 24,000. There's no clear "winner" anymore, but if I had to I think I'd give it to UP with BNSF a very close second.