Veracruz is a city and important port on the east coast of Mexico. In the 16th century, Hernan Cortez founded a town there. This town became a busy port and was the mani point of entry to Mexico for 400 years. On an island near the city is the fort of San Juan de Ulua. Today the fort is a museum but, in the past,it protected the port of Veracruz. It was a common target for attacks because there were lots of treasures of gold and silver. It's thick walls made it very hard to get into the fort and they are still standing today. San Juan de Ulua was also a prison for many years. It was also a prison for many years. It was almost impossible to escape from there because there were many sharks in the water between the island and the city of Veracruz. Nobody could swim from the from the fort and survive. The Mexican "Robin Hood", Chucho el Roto, was one of the many famous prisoners of the fort. Today, tourists can visit his old prison cell there