“Holt” is an old Germanic word (and English, with its Anglo-Saxon ancestry, is a Germanic language) for a wood, a forested area.

“Hanger” also comes from an old Anglo-Saxon term; it means a wood on a slope, like the forest on Wenlock Edge.

https://hokku.wordpress.com/2013/02/05/on-wenlock-edge-the-gale-of-life-and-emotion/