You just reminded me... I recently discovered that a website I made when I was a teenager is still online. I could still remember my username, was able to login, and was shocked to see the date stamps on the directory listing. The oldest file there is dated 19 May 1997 [0]. I intend to celebrate its 20th birthday in another ~16 months.

[0]: There's actually one slightly older (28 Apr 1997), but it's an image (.gif), not a .html file.