The group climbs the fire escape ladders higher, moving from landing to landing up the shell until they reach a platform high above the first level. The platform is actually the roof of another building, complete with red tile shingles and badly rusted rain gutters. The ladder has simply been bolted onto the building's side. From this makeshift platform there are two paths, one leading left and the other right. The one to the left is a metal catwalk leading to the enormous pipe you saw from below. From here you can see water stains and what look like depth demarcations along its side. It might have been some part of the guts of a dam, or maybe some long forgotten sewage pipe for a city of unreasonable size. Now it's a hive of demons. To the right is a semicircular bridge, a curving structure made up of sidewalk slabs that are held in place by metal I-beams sunk into Ouro's shell. It's like a path of stepping stones suspended hundreds of feet in the air. They're not too far apart, but each one requires a wide step or even a short hop to reach, so it's possible that a missed step could be fatal. Or whatever the equivalent is for what you are now. Past this curving bridge you can see a 4 or 5 foot wide concrete ledge in front of a wall filled with many holes. Each hole has been dug straight into the concrete shell by unknown means. You think that, just maybe, you might be able to hear human voices coming from that direction.
Past the bridge and that strange hole filled wall is the house you saw from below.