San Juan is an amazing city that everyone should visit at least once, but once you visit it the first time, you’ll want to go back time and time again. This historic city was founded by Spanish colonists in 1521 and has been continuously inhabited ever since.Today, it’s the largest city in Puerto Rico, and with a population of just over 352,000 within the city limits, it is the forty-sixth largest city under the jurisdiction of the United States. The metropolitan statistical area, which includes the suburbs surrounding San Juan, is home to 2.4 million.