Helston Castle - Credit: Wikimedia Commons
Helston Castle was a medieval castle thought to be built for Edmund, 2nd Earl of Cornwall in the late 13th-century, in Helston, Cornwall. The castle was ruined by the end of the 15th century, and sat at the bottom of Coinagehall Street, where the bowling green and Grylls Monument are now located. Although very little is known about the castle, it is speculated that the castle was a fortified manor house. Read more on Wikipedia
Source: en.wikipedia.org