This is the remains of the 'yellow steeple' of Trim abbey which stands just across the Boyne river from Trim Castle, the biggest Anglo-Norman castle in Ireland, built by Hugh De Lacy between 1172 and 1224.
Dan and I visited Trim during our weekend in Meath and it's one of the most impressive castles I've seen in Ireland but it is positively modern in comparison to some of the other monuments we saw that weekend which predate the pyramids of Giza.
Ring any bells? Trim Castle had a starring role in the film Braveheart, made over as the English town of York.
Too many castles, too little time!