The BBC reports on the oldest working door in Britain:

Archaeologists discovered the oak door in Westminster Abbey was put in place in the 1050s, during the reign of the Abbey’s founder, Edward the Confessor.

It makes it the only surviving Anglo Saxon door in Britain.

We most often think about the use of tree rings to study ancient climates (wide rings wet, narrow rings dry). But they’re also commonly used for archaeological and historical research, to date the time when structures were built based on the ages of the lumber used. I wrote a book about this.