Did you know the world's largest beaver dam can be seen from space, if by "space," you mean, "Google Maps"? It is in Alberta, Canada; it is a half-mile long; and it probably took two decades to build.
There it is, the World's Biggest Beaver Dam! Canadians have actually known about its existence since 2008, but because they are Canadian they wouldn't brag about it. In case you were planning a road trip, you should know that Google refuses to calculate directions between New York City and the World's Biggest Beaver Dam.