In 1989, British physicist Tim Berners-Lee invented what would be called the "World Wide Web." The first trials were held in December 1990 at the laboratories of CERN, the major research laboratory in Geneva, Switzerland that's better known today as the home of the Large Hadron Collider.
On April 30, 1993, CERN published a statement -- on the Web, no less! -- that made the technology behind the World Wide Web available on a royalty-free basis. (Specifically, this was the software required to run a web server, a basic browser and a library of code.)
And thus the modern public Web was born, at info.cern.ch.
The first website in the world was, understandably, dedicated to the World Wide Web project itself. (For Apple geeks reading this, it was hosted on Berners-Lee's NeXT computer.) The website described what the Web was and instructed how to access others' documents.
That original NeXT machine is still at CERN, but the world's first website is no longer online at its original address.
For many years, this URL has been dormant, inactive. It simply redirected to the web host root of http://info.cern.ch We just put the files back online, using the archive that is hosted on the W3C site. This is a 1992 copy of the first website. This may be the earliest copy that we can find, but we're going to keep looking for earlier ones.
History and technology nerds, it doesn't get much better than this. Want to browse the original site? Click this hyperlink, as the kids used to say.