Dead Links

The basic principle of showcaves.com is that each underground attraction has its own page. Links to this site are provided on the respective page at the foot. In general, it is beneficial to have cross-references to a topic; this is, so to speak, the basic idea behind the World Wide Web and hypertext. Unfortunately, there have been several unfortunate developments recently that render the concept of static links absurd:

Since around 2020, domains have been dying off in droves. The reason for this is unknown to us, but we suspect that many institutions simply no longer see the point of having a website.
Traditionally the tourist information was part of the municipality, the local attractions were published on the website of the municipality. Now the tourist info has its own page and the municipality removes all tourism related pages. This development is country-specific, but there are numerous countries with this development.
Many are switching to social media sites, especially Facebook.
Many are replacing their website with a portal, what was previously a static page with a URL, for example a cave tour, is now an event that comes dynamically from a database and no longer has a fixed URL. In the worst case, the URL leads to a single cave tour with online booking, and a page about the tour in general does not exist because everything is already included there. However, if this tour is fully booked or has ended, the link automatically becomes invalid. Such effects make linking to a portal almost impossible. If we determine that a website has been converted to a portal, we usually remove all links to this domain because it is no longer trustworthy.
Links to frameworks, such as the popular WordPress, may appear static, but they are actually parameters for the framework. If you use a different framework, or sometimes even if you simply upgrade, the URLs may change. We have seen everything, /cave.php becomes /cave.html or even /cave/. Or /foobar/?id=4711 becomes /foobar4711. It is particularly unfortunate if the framework already redirects the home page, e.g. from https://domain/ to https://domain/home-page/. If the framework is then changed, the home page will result in a 404 error.
When people lose interest or die, their websites disappear. This is particularly curious, as one would expect the community to take over when the websites are actually not private, but rather a service for a community. In our experience, this is unfortunately rarely the case.
Browsers now expect https pages, and pages without https are often classified as a security risk from the outset. Unfortunately, the technology is not yet very user-friendly. On the one hand, it involves costs, and on the other hand, the certificates have to be renewed annually. In addition, you can also make mistakes in the content of the certificate or have to generate a new one if you modify the domain name. This goes so far that websites are no longer accessible because the redirection from http to https has been built in, but the certificate is not valid. There are also some rather unfortunate cases where the https address claims that the website or domain does not exist, even though the http address works perfectly. This confusion will probably continue until providers are forced to provide certificates and update them automatically.
Unfortunately, switching to https usually also involves redesigning the website, which additionally changes the paths and file names. This is usually because the old technology no longer supports all requirements, or simply because the changeover is taken as an opportunity to do so.
Universities, which are regarded as bastions of knowledge, seem to have the same problem worldwide: a lack of understanding of the internet. They were the first to set up websites for all their departments and even their staff, but unfortunately these are even more short-lived than most private hobby sites. Staff accounts are deleted when they leave, departments are restructured or renamed, and the strategy for assigning domains is reorganised. But even the "long-term archive for digital materials to support teaching, learning, science and research", which some universities provided, were short-lived. If someone were to set fire to the library, there would be an outcry, but this is only data. We love linking to universities because the content is created by experts, so it is all the more sad when we have to delete them regularly because they are dead. If possible we use academia.edu and researchgate instead, which seem to be far more stable.
And finally, in non-English-speaking countries, many English translations are deactivated. On the one hand, it is often no longer worthwhile because foreign tourism has collapsed, especially in countries such as Russia. On the other hand, the effort involved in maintaining a bilingual website is considerable and often cannot be undertaken by volunteers. Finally, it is no longer necessary because browsers can now translate any language in the world when loading the page.

All these problems have led us to thoroughly review our own links. This applies to these link lists as well as to the individual pages. We have now deleted thousands of links, switched to https, or switched to the other language. In doing so, we are increasingly encountering the problem that Cloudfront and other protection mechanisms simulate broken links or use redirects to simulate that a link needs to be maintained. We have therefore decided to rigorously delete such links in future. Please use a search engine of your choice instead.