Hmmmm, I never seen the other underground routes apart from the one leading to the FAB. Gonna have to go exploring now 
@silva
Paragon Protector Elite are Dark and Fire rather than EN, Claws or Spines.
And yeah the underground tunnels are great
"Well, they found my diary today.
They were appropriately appalled
at the discovery of the eight victims
They're now putting it all together.
Women wrapped in silk
with one leg missing
Eight legs, one body, silk,
spider, brilliant!"
Not sure if anyones found this yet but i found a series of underground tunnels in grandville last night that are totally lag free regaurdless of how fast you move. Anyway i figured i should post this up since a lot of peeps suffer from horrid lag trying to go through grandville so this should help a bit. Oh and the tunnels are completly mob free
Although its not much but their are three entrances/exits the first one is near the main tower of grandville, the second is on the north beach near an archnos flyer and the third leads into the fab which i must say is an even more scaryer place than spider city well the underground part of it is anyway which is where the tunnel exit leads to. Also bumbed into some lv49 "paragon protectors elite" down there too if anyone knows what difference the elite part does for them i wouldnt mind knowing since normal PP's are hard enough as it is.