Vernii was the capital of Ix built underground.
The city was built upside-down, with groundcars, buses, and an aerial tube-transport system. The nobles and administrators lived in the upper stalactite buildings while workers and all the suboids lived below in warrens.
During the temporary takeover of Ix by the Tleilaxu, the city was devastated with walkways broken and buildings crumbling from the ceiling. Two of the diamond pillars supporting the immense rock roof had been blown, and the resulting avalanches had buried entire blocks of the grotto dwelling complexes.
That time, the city was renamed Hilacia.