I wish there were ruins like this in the MidWest. It's just remarkable to have these things in seemingly random spots. Too bad the country isn't old enough for it.
you might be surprised.
the further west you go probably less, yes. But east coast is LITTERED with ghost towns, and roads. Basically by 1900, the entirety of the East coast was deforested. cut down, pastures and towns built. we since then centralized more into cities, and had better agriculture, etc. State forests and national forests were established. look around the east coast, 99.9% of trees are less then 100 years old. the state and national forests were all farmland. pastures. that were donated back to the state/fed. then left to regrown.
Rock walls everywhere... because they were pastures. But also roads, and houses. and entire towns. the weather of then East coast destroys anything thats not stone though. and even some of that. Dam's as well are a factor. any brook or river on the East coast. is going to have many dam's for gristmills, sawmills, etc. might see ice making as well. but, busted dam's, or just 100 years of leaves/dirt/hurricanes/ice/snow, etc, theres rarely anything left but foundations. and even they are covered in dirt, debris, and often busted from falling trees.
you can't go a 1/2mile in the north east without coming across 1-10 foundations in the woods.
Abandoned Norwich state mental hospital.
weather is a big factor, but obviously so is construction materials. old castles built entirely from stone.. versus modern construction which isn't. Even steel is going to rust away before stone.
Mills as noted as well. again, every river and town in the East has abandoned Textile mills. Many of which are being renovated into apartments, etc nowadays. some burned down, some are just husks, others have collapsed. typically stone, brick, steel, and wood.
much of this stuff is still privately owned, or too dangerous to go near, so is fenced off. not like 1000 year old castles where the dangerous stuff is gone.