The main advantage of cast roads is that they are cheap to build. All that needs to be done to create a cast road is to move a device with a suitable transmutation enchantment over the intended path of the road. No materials need to be moved long distances, and road bed preparation is minimal in most places.
Cast roads are distinctive in appearance, and vary depending on local soil conditions. Over sandy soils, cast roads are glassy, and resemble obsidian if the soil is rich in humus or other impurities. Over clay soils, the road resembles brick or pottery. In loamy soil, the road has properties intermediate between the two and resembles porcelain.
Most cast roads are relatively thin and fracture easily with wear and age. However, such wear is acceptable because most forms of Locus transportation do not actually require a continuous paved surface. In the case of a hovercart, for instance, most of the weight of the vehicle is levitated, and hence virtually insensitive to ground conditions. It will move equally well on any surface; only the animal pulling it (such as an anathak) actually benefits from the road. The main purpose of cast roads is to inhibit the growth of vegetation, which would otherwise grow to obstruct the path. An additional benefit is that cast roads do not turn to mud in heavy rain, although it is still possible for a badly fractured and worn-out road to get washed away or to sink into the ground.