The Observation deck at One World Trade Center just opened its doors to visitors, and to commemorate the pretty exciting event, Earth Cam released the official time-lapse for the 11-year construction of the new building. Standing at a symbolic height of 1,776 feet with 104-stories, the time-lapse shows just how time intensive and difficult the process was. Thousands of high-def images were captured from October 2004 to Memorial Day 2015, when construction was officially completed.

Needless to say, it’s a pretty great celebration for NYC and the rest of the country.