Airu started as little more then a few caves carved out by Zora colonists. When a group of Hylian colonists set up shacks alongside these caverns they decided to coexist with the Zora rather than fight for control. After a time both forces worked together to grow and carve the city out of coralmold into the harmonious paradise that it is today. When the Kingdom of Hyrule and the Zora Dominion declared the half breed members of Lanayru perverted abominations and cut off their ties, Airu was set to be the capital of the newly made Lanayru Province. Various Zora Kings and Queens have ruled from the giant mushroom shaped palace for several centuries.
There are two main gates into the city, both of them facing to the west. Three long walls guard the north, west, and southern reaches of the city, while a deep river renders the city impervious to attack from the east (though really long ranged artillery might be able to set up shop on the eastern bank of the river and bombard from there). Once in the city there are three ways to get to the plaza. All paths on the ground level lead to a watery bottleneck, while scaling the walls lead to two upper mesas that descend from the north and south into the plaza area. While there are plenty of land passages for foot soldiers on all three of these paths, cavalry and siege equipment can only pass through the ground level method and are forced to tread slowly across shallow water. This makes is somewhat hard to invade the city with cavalry once inside the walls and as such infantry shine most on this level when evenly split up on the three paths to the plaza.
Oh where to begin with this one? A lot of love went into making this city, it's probably my current favourite and I'm not sure how I can top it. While the cities of the Zora Dominion did not really take much in terms of canon influence, I tried to stick much closer to preexisting material for the Lanayru Zora. Colour schemes and the general textures of everything were mostly influenced mostly by Lanayru Province from Twilight Princess, naturally. However some keen eyes will notice things from the Zora in Majora's Mask floating around this city as well. Overall I went for something that looks tranquil, calm, peaceful, and humble compared to the egocentric and bombastic architecture of the Zora Dominion.