A renamed farm town's foundations are mostly recent
The settlement that became Avon, Hampton, then White Lick, Smootsdell, New Philadelphia, and finally Avon, stayed agricultural well into the twentieth century and didn't incorporate until 1995, so most Avon foundations postdate that incorporation and were poured on the same clay-heavy Hendricks County soil found across the wider Carmel area.
Older farm-era foundations near the original township
The handful of older agricultural properties near Avon's original Washington Township settlement pattern, including land tied to the area's post-Civil-War farming history, carry foundations that have had far longer exposure to Indiana's expansive clay soil than the fast-growing subdivisions around them.