Colon
Enter the Panama Canal through the colonial city of Colon, which is home to many descendants of the Afro-Caribbean workers who helped build it. Its main attraction is the Colon Free Trade Zone, established in 1948 and housing over 1700 companies. You'll find anything and everything here, from pharmaceutical products to toys. While it's mostly wholesale, things such as cosmetics, clothing and jewellery can be bought individually. However, Colon is known to be dangerous, so exercise caution.
Gatun Locks
South of Colon lie the Gatun Locks, which raise ships up 29.5m from the Caribbean waters into Gatun Lake. One of three sets of locks along the Panama Canal, they are well worth seeing for their mind-boggling size - 1,820,000cu m of concrete went into their construction. A viewing platform gives tourists the chance to see the locks in action. The Gatun Dam is 2km from the locks - another crucial element of the canal.