aerial photograph of Saltwood Castle , a Norman Castle in Kent England UK. While much of what we see today of Saltwood Castle dates from the 12th Century, it is built on the site of a 5th Century castle and may even have been a Roman site. It was from this castle that the murderers of Thomas Becket gathered before carrying out their crime. The Castle was badly damaged in the earthquake of 1580, England's most severe recorded earthquake. The castle was eventually restored in the 19th Century and is now a private home.