Incidentally, these are the balance ponds which fed the castle hothouses and the main lake which you will see later (the main lake in turn provided water for the iron works). The hothouses grew the first pineapples in Wales which is quite amazing. If you visited Merthyr today and someone told you that pineapples were once grown there you would be inclined to accuse him, (for it would have to be a him) of suspecting you of being gullible.

Anyway back to your history lesson.