In the belief that the surname Caldwell derived originally from the Anglo-Saxon place name, caeld weille, meaning artesian well, I was frustrated by an inability of finding any such place name or similar name in modern day Germany.

Today I discovered that In the Black Forest region of Germany, is the town of Calw (158,000 inhabitants) , known for its four therapeutic baths. (www. landkreis- calw. de/&prev=/ search% 3Fq% 3D calw%26hl%3 Den%26sa%3DG The Black Forest, or Schwarzwald, borders on Switzerland on the south, on the Neckar River to the East and on France to the West.

Bertha of Calw, 12th century sister of Pope Victor II, has been linked as kin of Sir Adam Mure of Rowallan, Scotland.
http://freepages.genealogy.rootsweb.com/~jamesdow/s064/f100336.htm © 2002 David Andrew Caldwell