The long-planned Panama Canal expansion was marked by fireworks, music, and cheers on Sunday as a Chinese cargo ship from COSCO became the first to pass the new, wider Cocoli Locks at the Pacific side of the canal.

Such fanfare was also in the air 102 years ago, when canal first opened on August 15, 1914 after 11 of construction, and decades of planning. To see how Panama Canal has changed over the years, move the center slider left and right.

Miraflores Locks

 
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The photo on the left shows the Miraflores Locks in the Panama Canal sometime between 1909-1919 (Photo: Library of Congress). The photo on the right shows the same locks today. Coming from the Pacific side of the canal, the Miraflores Locks are just before the newly expanded Cocoli Locks which uses new hydraulic technology and reuses water from several other locks.

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The left photo shows the east chamber of the Miraflores Locks, east chamber (Photo: Library of Congress/Detroit Publishing Co.), also sometime between 1910-1920 as the “Panama of New York” steamship passes through. The photo on the right shows the same position today.

Planning for the current expanded canal began more than a decade ago, after the United States handed sovereignty of the canal to Panama in 1999. Prior to that, the U.S. had built and run the locks for 85 years.

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The photo on the left side shows a nearly completed Miraflores Locks control house in 1913 (Photo: Library of Congress/Byron Co). The photo on the right shows the same building which now houses the Miraflores Visitor Center.

Map Pacific side of the Panama Canal

Balboa, Panama

 
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The left photo shows two women standing on a hill overlooking the Pacific Ocean entrance to the canal in 1916 (Photo: Library of Congress). The right photo shows nearly the same position, taken by CCTV America Correspondent Roee Ruttenberg last week.

Watch the first ship pass through the expanded Panama Canal on June 26, 2016

People celebrate the opening of the original canal in 1914

Crowd at Panama Canal opening ceremony with some children holding U.S. flags possibly in 1914. Photo: Library of Congress, John Barrett Collection.

View more historical photos of the Panama Canal

View historical footage of the story of the Panama Canal