Final answer:
Ships traveling from Balboa to Colón on the Panama Canal pass through a total of six locks on the original route. The Panama Canal, completed by the US in the early 20th century, is an engineering marvel that significantly reduced the maritime journey between the Pacific and Atlantic Oceans.
Step-by-step explanation:
Ships traveling from Balboa on the Pacific side to Colón on the Atlantic side of the Panama Canal must pass through a series of locks. Before the expansion in 2016, this involved three locks at the Gatun Locks, one at the Pedro Miguel Lock, and two at the Miraflores Locks, making it a total of six locks each way. The expansion of the canal provided a new set of locks that can accommodate larger Panamax container ships, known as the Cocoli Locks on the Pacific side and the Agua Clara Locks on the Atlantic side, adding more options for ships but not changing the number of locks traveled through on the original route.
The Panama Canal's construction is a significant feat in engineering history, beginning with the French in the late 19th century and completed by the United States in the early 20th century, overcoming geographical challenges and reducing the maritime journey significantly.