From RocksfallWiki

Lyre was originally a brick and mortar city built as the hub of the empire. Its beauty was known through out the world. All the brick were whitewashed every year to add to the attraction. Lyre stood as the symbol of the empires richness and power. Since the fall many things of changed. Soot and grime has covered the city. The mountain that the city was carved from has become honeycombed with the hub of the tram system between all cities and outpost. Huge towers now eclipse the sky, with their landing pads for airships. It not uncommon for a runaway invention to careen down the streets.

Like all cities more and more walls have been built outwards to help the overflow of people. The center area is the technology hub and tram repair area. 2nd walled area, are living quarters for artificers, the 3rd wall is now used by miners and resource gatherers (including eatable roots) from the tunnels. The next section is merchants and urban areas. Lyre has not had any major attacks on it from the green. Some say its because it has always been built from the mountain and plains, that surround the area.