Reims is a city in northeastern France's historical Champagne-Ardenne region. It's the unofficial capital of the Champagne wine-growing region, and many of the well-known champagne houses headquartered there offer tastings and cellar tours. The 3rd-century Porte de Mars triumphal arch marks the town's time under Roman rule. For more than 1,000 years, French kings were crowned at its Cathédrale Notre-Dame.