Prince of Wales/duchess of Cornwall Home: __ House

Puzzle 20 of National Crossword Day Hard Pack

Question is: Prince of Wales/duchess of Cornwall Home: __ House

and the answer is: CLARENCE

Word Meaning:

CLARENCE — A kind of carriage popular in the 19th century; a four-wheeled horse-driven vehicle with a glass front and room for four passengers.

Definitions from Wiktionary.