Say you had to host the information as a set of static HTML documents and you wanted them to remain accessible for as long as possible; what strategy would give you the best odds?
The Internet Archive would be the easiest way, but a boring answer. You're trusting another organization to maintain your data, but it's about as certain as any other option to be available in the future.
You could trust Cloudflare or AWS to keep an storage bucket alive, but then you've got to continue paying for it, and there will almost certainly be some changes in the next 500 years that would require a human touch. Who knows if AWS will still be around, or if its new parent company, Yahoo-Facebook-Intel, will drop contracts if you don't log on daily to 'Oculus Space'. My point is, The Internet Archive might be your best bet if you rely on another organization to keep the site up.
If you did it yourself, you'd need - a stable file format (SIRF?) - multiple backups and copies, even on the same disk - very stable, simple computer to serve the content - maybe like, a Raspberry Pi-like system submerged and sealed in mineral oil? - static IP address to host from - this might be the dealbreaker for a DIY solution. You'd need to rely on other services - A local network that can be connected to...even after 500 years of changes to networking protocols.
Even with a DIY approach, you'd be relying on a trust of some sort that could handle replacing parts as needed. You could invent an analog titanium read-only storage disk with your data encoded on it, but even if you have bullet-proof hardware, you still need to allow people to connect to your server...and that is the least predictable part of the problem.
If enough people are interested in preserving content like this, a block-chain storage solution could work. You'd be relying on the system still being active in 500 years, so you'd need multiple generations of people all using the same blockchain to preserve their data. Kinda like a decentralized Internet Archive.
Starting maybe from the transistor, if you're insistent on the full experience of loading the website from a browser with HTTP on TCP/IP networking.
Otherwise you can just etch the HTML in stone with a brief explanation of what the tags mean (eg. part of the HTML spec). Generally popular languages can survive 500+ years, so one can safely presume that some people 500+ years later can understand our English if they put in some effort.
.. I don't know why anyone would presume the web in any form would exist in 500 years. It would be fortunate if humanity as we know it still exists in 500 years. We are so capable of wiping out ourselves with various techs (whether intentionally or otherwise) that the odds are not really that great.
