The Abandoned Houses of Instagram

People lived in these places once. What mysteries did they leave behind?

Vines crept up the house. It looked like it was about to cave in. The Colonial in Roscoe, N.Y., a hamlet of the Catskills, was decrepit — which made it all the more appealing to Bryan Sansivero, 36, and a friend, who had arrived before dawn. They entered the musty, empty dwelling, which was not really a dwelling because no one dwells there, and sat in the dark for about half an hour until sunrise. Soon, the living room was aglow and its contents revealed: antique furnishings, a fireplace with a knickknack-lined mantel, and, most shockingly, a tiger skin rug (the creature’s mouth agape) and a hunting rifle. “We were like, this house is insane. How is this just sitting here and completely abandoned like this?” Mr. Sansivero said. Despite the dilapidated condition, including peeling walls and an unpleasant kitchen, the house was in pretty good shape. He snapped photos and later shared them in a Facebook group dedicated to old houses, where his posts stir emotions ranging from nostalgia to sadness to skepticism that the house was actually found in that condition (Mr. Sansivero said that the houses’ belongings have typically been staged by previous visitors but that he only makes minor adjustments).