There are more than 180,000 historical markers throughout America, and many of them tell only partial truths. Over the past year, NPR has analyzed crowdsourced data to uncover some of those errors. Many were strange, funny or silly — like a sign that marks the home of a world-famous Santa Claus school in Albion, New York, and a marker in Arizona that pays tribute to a donkey that drank beer. But many paint a fractured version of history: 70% of markers that mention plantations do not mention slavery, and there are 500 markers that describe the Confederacy in glowing terms. Here's more.