Yahoo paid $3.57bn for GeoCities in 1999
Yahoo is to close its personal web hosting site GeoCities later this year.
In a statement, the firm says it will no longer be accepting new customers and will focus on helping "customers build new relationships online".
Yahoo bought GeoCities for $3.57bn at the height of the dotcom boom in 1999.
At its peak, GeoCities boasted millions of active accounts, but it has since fallen out of fashion, with users migrating to social networking sites.
Yahoo says that existing GeoCities accounts will remain live for now, although it stresses that users should start looking for alternative sites.
"You don't need to change your service today, but we encourage anyone interested in a full-featured web-hosting plan to consider upgrading to our award-winning Yahoo! Web Hosting service," the firm said in an online post.
The closure of GeoCities spells the end of Yahoo's free hosting, although other services - such as e-mail accounts - remain unaffected.
Rupert Goodwins, editor of the ZDNet website, said the closure of GeoCities was the end of an era.
"I think GeoCities was the first proof that you could have something really popular and still not make any money on the internet.
"It was a fascinating experiment in the pre-industrial era of the internet, but after the initial exuberance on what the web could do, it turned out to be more complicated than just giving them free hosting.
"You need to give users tools to actually do things and make things simple, one of the reasons sites like Facebook and MySpace are so popular," he said.