The United States, with its extensive history, has given rise to some striking and unique architecture. From preserving local history to showcasing some of each region's unique cultural quirks, these 51 buildings across the US are worthy of being tourist attractions . Defining what we consider to be the "coolest" is hard. We evaluated every state on its own terms, and we've found that the architecture across all 50 — and Washington, DC — is as diverse as its population. In states like