Oddly they've taken out the (c) 1997 part, maybe to make it not seem as ancient? I suppose it's still reasonably relevant; not much of this basic information has changed. Heck, Water Tunnel #3 is still under construction.
I'm pretty sure the audio is RealAudio encoded though can't confirm as I don't have the codec installed (does anyone anymore?). This is just a guess based on the .ram file extension.
Still cool to see how engaging you can make a site using 10-15 year old technology. Content is king.