Boston and New York City have shared a rivalry as cities since before the American Revolution. For more than a century after its founding, Boston was arguably the educational, cultural, artistic, and economic power in the United States. Its location as the closest American port to Europe and its concentration of elite schools and manufacturing hubs helped maintain this position for several decades. During this time period, New York was often looked down upon as the upstart, over-populated, dirty cousin to aristocratic and clean Boston.