Random curiosity, but it looks like more than a few pages about Pathfinder and the Sojourner rover are still online more than twenty years later, and probably last updated in '97 or '98 on average.

Here's a neat one: https://mars.nasa.gov/MPF/roverctrlnav/rovercntrlnav.html

Many are also good examples of what the Internet looked like two decades ago :^o.