Knowth is the largest of the Boyne Valley passage tombs and dates to circa 3000BC. Since 1962 excavations have been continuing and the magnificent tumulus exterior is now open to the public.
Knowth is more complex in its construction containing two passages and being surrounded by seventeen satellite tombs. The great tumulus at Knowth is comparable in size and shape to Newgrange, standing twelve metres and having a diameter of some sixty-five metres. The mound is surrounded by up to one hundred and fifty giant kerbstones, many of them beautifully decorated.