Nothing lasts forever, not even concrete:
The downspouts are obviously more recent than the splash blocks, but the whole shopping center wasn’t more than a few decades old. Rain isn’t nearly as acid as it used to be, but it still eats away at concrete.
After about two decades, though, even high-quality concrete goes bad:
That’s the upper surface of the Rt 376 bridge at Red Oaks Mill, with a fragment of the corroded lower edge still dangling over the Wappinger Creek:
Mostly, we manage to bike around the decayed infrastructure.