D&D Random Encounters for 5E - Ruins
Encounters might be a meeting with a patrol of guards at an old shrine or a familiar looking for aid. It might be an ambush in the wilderness, a stand-off in the city or a monster in the Underdark.
Ruins might be a haunted mansion, an abandoned village or a crumbling tomb, among broken masonry, fallen pillars and piles of debris. They are home to restless spirits, strange oozes, desperate cultists and arcane experiments.