The least populous state capital in the United States is Montpelier, Vermont. With a population of just over 8, 000 people, it is the smallest state capital in the country. Montpelier is located in Washington County and is the only state capital without a McDonald's restaurant. It is also the only state capital that does not have a major interstate highway running through it. Montpelier is the capital of Vermont, a state known for its beautiful scenery, outdoor activities, and maple syrup production.