Found: A Map of the Entire Internet, As of 1973

(via Atlas Obscura)  In the very early years of the Internet, back when it was the secret and very small ARPANET, which had started in the late ’60s, consisted of only four locations. By 1973, it had expanded to a small handful of government labs, research universities, and private companies—but still so few that the entire network could be mapped on a single sheet of paper.