Panama City is the capital of Panama, and also its largest city, and was founded in early 16th century, after which it became a hub of shipping and industry quickly, largely in part to its prime location between the Atlantic and Pacific oceans. Panama's main city was initially built by the Spaniards in the late 17th century, now called the Casco Viejo, or Old City, as fortress to keep pirates out. As a result, there are still large stone structures than hint of the city's history, including the stone dungeons built into the sea wall, known as Las Bovedas, or The Vaults. Panama is probably most famous for the canal, built at the turn of the 20th century, which enabled shipping directly through the city and thereby cementing Panama City as a center of international commerce forever. From 1980 until the mid 1990s, Panama experience political turmoil and a downtrodden economy, which caused the population growth to lessen considerably, with Panama City's population growing by only 30,000 people, however, by 1996, the population exploded once again as commerce picked up in response to a new and settled goverment, increasing by approximately 250,000 people in the capital alone.