Right I edited the railroad from Fenris-Trashpire. It now loops and stops at both ends with a button to continue. It also stops at the catacombs, an almost 2000 metres tunnel of about 20x20. Don't randomly go wreck things there (no TNT either!) and don't throw torches all around, or I'll hide the entrance as fast as I gifted access to the server.

WARNING: The hatch to the catacombs is one-way only, it goes down. To go up one needs a password, can walk it all the way through to either one of the not-yet-so-clear exits or /warp and /home to a waypoint. Soon there'll be a huge nether-gate, unpreceded by any previous endeavours to reach a different station than the Kastra-built one. It should offer a new nether area to harvest glowstone etc from, given that fortunately placed glowstone around the netherstation has been taken by now.