Col. William Gorgas has successfully eradicated the disease from the isthmus. 1906 U.S. Senate approves project as a lock canal. Roosevelt, in the first trip by a U.S. president outside the country while in office, visits the site on November 6. It is still a slide surveillance area. 1909 First concrete poured for locks at Gatun on August 24.
Locks take four years to complete.
1913 Steam shovels digging from opposite sides of the isthmus meet in the middle. Last rock lifted from the canal on September 10. Earthquake shakes a scare into the builders on September 30, but no damage was reported. President Woodrow Wilson pushes the button that relays, via telegraph, the signal to blow up the center of the dike that was keeping Atlantic waters from Pacific waters. Official opening day is August 15.