It could be a selection effect too. The Greek world is unusually well-studied. This tunnel was discovered and excavated in the 1800s by German and French archae

It could be a selection effect too. The Greek world is unusually well-studied. This tunnel was discovered and excavated in the 1800s by German and French archaeologists. It helps that the Greek world was close to Europe and has a large literary legacyy (partially because of continuity through Rome). Compare that to ancient Mesoamerican or African or Indian civilizations, which have a relatively shorter period of intense study, but every decade we seem to come away more impressed. For example, Nazca puquios are still a bit of a mystery but are extremely sophisticated tunnel and irrigation systems: https://en.m.wikipedia.org/wiki/Puquios https://en.m.wikipedia.org/wiki/Puquios