How do I address a letter to the Queen?

I've received my fair share of celebrity mailing address questions over the years, but this one was so fancy! Needed to clarify which Queen, of course (turned out it was Elizabeth II of England). Apparently Buckingham Palace has no need for a street address. For those interested in sending a letter to the Queen, here's a link to the Royal Family contact page: https://www.royal.uk/contact

LettertotheQueen.jpg