Knowth

Knowth is the largest of the three great Boyne Valley mounds, built around 3200 BC, and it differs from Newgrange in two ways that matter. It has two passages rather than one, entering from east and west and nearly meeting in the middle, and it is ringed by around 127 kerbstones, most of them carved - together with the art inside, that amounts to roughly a third of all known megalithic art in Western Europe, including the celebrated stone sometimes read as a lunar calendar. Eighteen smaller satellite tombs surround the main mound. The site was reused repeatedly: Iron Age burials, an early medieval settlement with souterrains, and a Norman motte on top. The passages are not open to visitors - unlike Newgrange, you cannot go inside - but you can walk on the mound and around the full kerb, which is where the carving is.

What you actually see

• The kerbstones - around 127, most carved, ringing the mound.
• The two passages - east and west, unusual among Irish tombs.
• The satellite tombs - eighteen smaller mounds around the main one.
• The later layers - Iron Age burials, early medieval souterrains, a Norman motte.

When to go

April to October for the fullest tour schedule. Access is only by shuttle from the visitor centre and slots must be booked - turning up without a booking often means being turned away.

Honest expectations

You cannot enter the passages at Knowth, which disappoints people expecting the Newgrange experience. Access is by timed shuttle only; walking or driving to the site is not permitted. Tours are cancelled in bad weather at times.

Nearby

Newgrange and Dowth are the other Boyne mounds; the visitor centre serves all three.