Exiting the Grand Hall into the bailey of the castle, a little over 135 yards away and slightly to the right, stands the Gate House. Normally its fortified gates are open and the double portcullises withdrawn.
The Gate House is huge, some 180ft high and 250ft wide, with four 50ft diameter corner towers standing some 30ft above the main structure. The 20ft wide 20ft high arched tunnel, through the 100ft thick structure, has 2 sets of iron reinforced bound oak doors, one at each end, and each backed by a portcullis.
Typically there are four guards on duty at end of the tunnel and typically they will ignore those leaving the castle.
The first thing that you notice, other than the down slope, and the smaller gatehouse off to your right is the 80ft high wall, possibly some 330ft away.
The 'street' slopes down for about 150ft as it passes the buildings on the left, although these are set back in line with the end of the Gatehouse, before nominally leveling out.
Descending the slope, there are 2 options. To your right is the smaller gatehouse, whilst to your left the street appears to bend away from you to the left. Perhaps about 10% of the actual buildings in the vicinity of the gatehouse are in-use/occupied.
Turning left the street continues to curve around to the left, circumscribing both the castle wall beyond the street facade to your left and the plateau. After about 300 degrees the black wedge of the Abyss looms back into view, along with a pair of gatehouses, one directly ahead and one to your right. Unlike most of the buildings along the street you've just traversed, there are a few buildings here that appear to be in-use/occupied as opposed to appearing completely deserted.
If you choose to continue straight ahead, there by traversing the gatehouse directly ahead, you end up in what appears to be in some sort of short dead-end street which runs to your right. Alternatively, taking a right turn, there by traversing the gatehouse on your right the street slopes downwards about 30ft as it traverses the buildings set back to your right. After about 150 the street turns right at the bottom of the slope.
As on the previous level the street traverses a 300 degree arc, before ending in a pair of gate houses, one to your left, and one straight ahead.
As previously the gatehouse straight ahead leads to a short dead-end street, where as the gatehouse to the left leads to another street which turns left. The buildings in this street are different to those on the previous 2 levels being much larger and more substantial. At least one of the buildings looks like it may be some kind of administrative center, whilst several of the others look like they may be warehouses of storage facility.  The architecture of all the buildings appears to be 17C Medieval European in nature.
There are 7 levels to the city in total, before the final gatehouse leads to the switchback which descends to the canyon floor some 700ft below.
The nominally distance between the walls on each level is 330ft, with a central 'road' through the middle. Offset 3ft from the center of this 'road' is the 'flagged' section of the road which is 12ft wide. On the down slope side is a raised flagged walkway 4ft wide. The first 12" of this serves as the rainwater sewer, and water can run off the road surface into this via 3" diameter holes every 3ft. On the 'up-slope side' there is a 6ft wide compacted gravel road raised 3" above the flagged road way, and bordered by 3" wide kerb stones. Whilst the flagged roadway is designed for horse drawn traffic, such as carts, the gravel roadway is designed for horses being ridden. Outside of this gravel roadway on the up-slope side is another 3ft wide flagged pedestrian walkway.
The 'circumference' distances of the roadways between gate house varies according to city level. Level 1 is taken to be the level closest to the canyon, and level 7, the level below the castle.
There are 3 levels to the switchback, each level descending just over 230ft. The gradient is 11%, each leg of the switchback being about 0.4 miles. The switchback is 9ft wide which allows carts to pass one another with care.
From the city gates, you look out over a wide canyon. In the distance, perhaps  2 miles away a bridge is visible which spans the river which cuts the canyon in half radially, and about 2 miles beyond that the far wall of the canyon. The road appears to snake up a set of switch backs on the far side before disappearing from view into a forest. Between the city and the river a sparse array of buildings dot the landscape, marking the positions of farms which support the city. Additionally there is a small cluster of buildings adjacent to and clustered about the city side of the bridge.
The bridge is made from cut stone, and is an semi-elliptical arch span construction. The bridge itself is 951ft in length, the river being 850ft wide and about 8ft deep. The bridge consists of 19 39ft elliptical arch spans supported on 6ft wide piers. The bridge rise is 12ft.

At the base of the switch back, on the Abyss side of the city, at effectively the base of the sewer run, are a pair of mills driven from the flow, which exits onto an overshot wheel.
These mills are the primary grain mills for the city. The sewage is then discharged into a reed bed and gravel system, before flowing into the river a short distance before it disappears into the base of the plateau.