The Hadley Hills are a rugged glacial moraine located in The Thumb of Michigan, that extend from northern Oakland County and into southern Lapeer County.
Map of Hadley Hills, Hadley Township, MI 48462, USA
The hills surround the village of Hadley; the highest points and most prominent outcroppings are located in Hadley Township, in Lapeer County. The Hadley Hills are an extension of a larger collection of hills which are attributed to other geologically related moraines, that run in a southwesterly direction from northern Lapeer County and actually stretch as far south as northern Indiana, and Ohio. The southern portion of this moraine is known collectively as the Irish Hills. This glacial ridge, and plateau system, creates some of the highest points in southern lower Michigan, is dotted by numerous lakes, and provides the Detroit Metropolitan Area with many of its recreational areas, parks, ski resorts, and beaches, including the Ortonville Recreation Area, Metamora-Hadley Recreation Area, the Holly State Recreation Area, and the Mt. Holly, and Pine Knob ski areas.
The Hadley Hills were created in a different geologic process from the rest of the moraines in the system, which were created by the advancement and retreat of the glaciers. The Hadley Hills, are instead, a veiki moraine, which is produced by the melting of leftover, or "dead" glacial ice, which created a plateau of glacial debris, instead of a typical ridge. This accounts for the numerous basin lakes, sinkholes, and unusual shape, and rough terrain associated with the hills.
The hills provide habitat for wildlife, and are popular with hunters and fishermen. There is also a network of trails used by hiker, snowmobilers and also for horseback riding.