From a civil engineering perspective, across thousands of km of Roman roads a statement like "and sometimes needed excavations up to 2m deep" would be true but

From a civil engineering perspective, across thousands of km of Roman roads a statement like "and sometimes needed excavations up to 2m deep" would be true but uncommon. ( There's always going to be that vast length of bog, to long to justify going around, that needs crossing ) The main point here is that other large road systems existed at the same time as Roman roads.