The European royal reportedly paid over $750,000 (£615,000) for the East Falls estate and spent over an hour touring the dilapidated mansion on Tuesday (25Oct16).
The home is a big part of his family’s history – actress Grace Kelly was staying there when she accepted a marriage proposal from Albert’s father, Prince Rainier.
His cousin John B. Kelly III claims the old place, which had fallen into a state of disrepair before the prince bought it, could become the base of the royal’s charitable foundation and house a small museum honouring his mother, who died in 1982, according to the Daily Mail.