a strange tunnel

i was looking for a flat surface to build one outpost but i also found a huge tunnel with no owner and not claimed i can claim near it?

 

I think you could because it's not claimed and I don't think it's built by another either unless it's Admin built through World Edit.
I think it's just a randomly generated tunnel as I've been there before when trying to raid and the tunnel was endless. I did not reach the end because I gave up trying to get to the end.

 

I Would, that tunnel (water thingie) is really long it goes around the whole world

 

I’ve seen many towns claim near or over this tunnel I think it’s there to connect towns as further up someone has signposted it

 

As staff have already answered your question, I'll move this to resolved. ​