CONFIRMEDDate confidence: CONFIRMEDStated as firmHow firmly the source words the date: confirmed, scheduled, estimated, delayed or unverified.Show all CONFIRMED pins83% CONFIDENCEOverall confidence: 83%How well the pin's source and references back up its dates.Weighted average of how firmly 4 references, the source included, support the pin's start and end times; a reference counts half as much for every 180 days older than the newestShow all pins at 75% confidence or better
Happened as dated, per the source[1]: "opened to the public in Washington, D.C., on this day in history, Oct. 9, 1888".After decades of stalled funding and a visible change in stone partway up its shaft, the Washington Monument finally opened its doors to visitors in 1888.
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