We advise booking the earliest slot at Brú na Bóinne. The river valley often holds mist until nine, and the visitor center will be tranquil. By the time larger groups arrive, you will already be finishing your loop above the Boyne.
Our preferred onward journey is lunch at the Eastern Seaboard in Drogheda, then a coastal drive to Clogherhead. The Boyne Valley rewards a deliberate, half-day exploration.