Gruna sites of interest
The Trader's Road (route from above)
A busy, and incredibly large tunnel road leading down into the city. Rather than allowing carts down, a large train (think the vertical ones in Switzerland) are inspected and loaded above and brought down. This train is powered and run by a spirit called Hapstance.
Ald Gruna (first level)
It is not very large, but every itch of space is used to create domed towers within the natural cavern. The building along the edges follow the shape of the rock, rooms carved into the rock rather than built on. These are mostly warehouses for food and weapons (although nothing of real value is kept here), and each family is given one or two (depending on the size of the clan) for storage. Many of these lie abandoned or forgotten about for years, and a few hide the secret air vent to the surface. This is also where someone might stumble on the remanent of the resistance during the War, or signs of Gnomish spies.
Propre (second level)
The aging populace mostly live in the upper city - not be design but purely because the younger people moved down into the new homes below. Almost all dwarven children can be found here, and this level is more spread out that above, with open places for meeting and playing being more common. The roads are not as wide than above, with trade coming from above in lifts between the waterfalls, back into the rock and moved out from there, or on ziplines coming from the backside of the dam's wall. Cooking and eating is more communal down in this part of the city as a result. The evaporation from the water above and below, and being lower and further away from the Trader's road means that the walls here are almost always wet and 'rain' is quite common. Awning cover most roads, angled to lead the water back into the drainage gutters. Dwarves from other dwarven cities, along with their families, are sometimes allowed into this part if they are being considered for an exchange marriage as part of the courtship rituals but it is incredibly rare.
Siegehold (third level)
The entrance is down a large stairs that lies hidden behind the second level that is easily blocked and defended. An air duct and lift used to lead to the surface from here, but it is closed off at the top and spikes and steel mesh all along it. People do live here, it is known as the Bachelor's quarters and is where all unmarried, but adult dwarves live in segregated dorms. This is where the journeymen live, at the end of their apprenticeships before they have completed their masterpiece and fully joined their trad, along with those who have applied for a marriage.
Unnamed fourth level
It is for experimentations. Forges down there work on dangerous items, druids test the water and experiment on modified species for food, purifying, oxygen production and other reasons. Monsters are brought from elsewhere for the last part of training for the Fishermen, and armed section of the Jurors. This is where the prison is also, and Fishermen will travel down here from above occasionally to practise before heading down further, to the uninhabited crab grounds, to hunt larger prey.
The Stairs
The stairs that started behind Propre continues downwards, lifts and steps carrying the dwarves down and away from the city into the very depts of the earth, where the water is plentiful, but the dangers present make it too dangerous to live. Riches unimaginable lie waiting in the dark.
The Geode
A giant geode was recently discovered with crystals that seem to have slight magical powers, and tests are being done to see it these can be used as air purifiers, so the remaining vents to the outside world could be closed. Any failures are taken away to be forged into items for trading.
The Tunnels
These tunnels are made in search of air and water, but often lead to deadly encounters instead. Failed tunnels are often collapsed or closed off, but not always fully and burrowing and seeking dangers often come up from the dark.