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Along the route of the canal there is a series of 3 sets of locks, the Gatun, Pedro Miguel and the Miraflores locks.
At Gatun there are 2 parallel sets of locks each consisting of 3 flights. This set of locks lift ships a total of 26 metres. The locks are constructed from concrete from which the aggregate originated from the excavated rock at Culebra. This was then crushed and used as aggregate. In excess of 1.53 million cubic metres of concrete was used in the construction of the Gatun locks alone.