The women in the photo were Les Horribles Cernettes, an all-female "high energy rock band".
But it turns out the Cernettes' promo shot wasn't the first photo on the web. In fact, no picture was.
Silvano de Gennaro, a software engineer at CERN at the time, who both managed the band, wrote their songs, and was dating band-member Muller, told BuzzFeed in an email: "The web was born with pictures already inside it."
At this point, the internet had already existed for a couple of decades and contained "millions of pictures", says de Gennaro, so it doesn't make sense to talk of a "first" anything on the web. "This is why there isn't a single 'first picture', like there isn't a 'first line' or a 'first page'."
"At the time you didn't 'upload' a picture, you just copied it to a folder on the server and created a link to it by typing an HTML line," he says. "It was like programming, and we were all programmers."
It was de Gennaro who was responsible for the band's photo ending up on the early web.
Tim Berners-Lee was about to publish a web page about CERN clubs when he saw the picture on Silvano's computer and suggested it would make a good addition.
The Cernettes performed at CERN social gatherings and conferences, singing '60s pop as well as their own songs.
Here's a music video for their first song, "Collider".
Despite the farewell gig, the band are not ruling out more shows and even a new album at some point in the future.
But it'd have to be for a "special occasion", says Silvano. "Cult bands do that."
If you want to keep up with any developments, you can follow the Cernettes on Twitter and Facebook. They also have a website. But if you prefer a more authentic mid-90s internet experience, their CERN-hosted website from 1994 hasn't changed much since then.