I've been the editor (a volunteer, unpaid) for the Urban Exploration category at the Open Directory Project for more than ten years. The category was founded by darkpassages but at some point she left and I kept it all going. AOL bought the directory a few years ago but dumped the directory last year. Some of the editors have kept it going on their own servers, at their own expense. We did have to change the name (and the mozilla mascot is now a red squirrel).

So the link is now - https://curlie.org...Urban_Exploration/

The urbex category is up to date other than a broken link for a Japanese urbex site which I am hoping will turn up again. Submit your sites, or changes to existing listings, and they will get looked at. I don't list 100% of the sites which are submitted or found by myself. They do need to be readable, on topic and at least kind of active or not brand new with almost no content. It costs nothing to have your site listed, it has always been a free directory run by volunteers.

If you are interested in joining up to be an editor in the directory, there is an application on the site. A great place to start is your own town in https://curlie.org/Regional/ In most cases you can list your own site by the Regional location and you get to know how things work and see if you want to stick around. I've got Urban Exploration handled but there are a lot of other categories that need help.