Buford. WY the zip code with the states smallest population. I was doing a road trip along the old Lincoln Highway from WY through NE and of course had to find Buford. This tiny town has two big claims to fame. First, with a population of only 1 person, it’s the nation’s smallest town. Sitting at 8,000 feet, it’s also the highest town in elevation on Interstate 80 between NY and SF!