Inselberg

An inselberg or monadnock (/məˈnædnɒk/ mə-NAD-nok) is an isolated rock hill, knob, ridge, or small mountain that rises abruptly from a gently sloping or virtually level surrounding plain.

The term was coined in 1900 by geologist Wilhelm Bornhardt (1864–1946) to describe the abundance of such features found in eastern Africa.

However, it has since been used to describe a broader geography and range of rock features, leading to confusion about the precise definition of the term.

A 1972 paper defined inselbergs as "steep-sided isolated hills rising relatively abruptly above gently sloping ground".

[5] Monadnock is derived from an Abenaki term for an isolated hill or a lone mountain that stands above the surrounding area, typically by surviving erosion.

This process leaves behind tors perched at their summits and, over time, a talus-bordered residual known as a castle koppie appears.

[27]: 326–327 [28] The inselbergs of Eastern Africa tend to be a refuge for life in the Serengeti of Tanzania and in the Masai Mara of Kenya.