The road layout of Los Angeles seems to be like domains in crystals. The roads try to grow with a regular orthonormal layout, streets one way, avenues the other way. As the different areas expand they meet up, revealing that the alignments are not the same, and domain boundaries are the result, with interesting distorted street layouts. And once hills become involved, the layouts are epitaxal. That is, if semantically you're allowed to be epitaxal atop something that isn't even a regular lattice.
