There is scattered evidence that Monasterboice had pre-Christian sacred significance as well.
According to legend, Saint Buithe ascended directly into heaven by a ladder lowered from above.
The settlement was captured by invading Vikings in 968 AD, who were later expelled by Donal, the Irish high king of Tara.
The monastery there was an important center of spirituality and scholarship until the Cistercians arrived at nearby Mellifont Abbey in 1142, after which Monasterboice declined.
Monasterboice is chiefly known for its many spendid high crosses.
Like murals and church sculptures, these magnificent examples of Celtic art brought the Bible to life for the illiterate.
The cross near the entrance to the site is Muirdach's Cross, dating from 900-923 AD. Standing 16 feet tall, it is named for an abbot mentioned in the inscription on the base: "A prayer for Muirdach for whom the cross was made."
The carvings have not all been identified.
On the eastern face, from the bottom up, they appear to represent the Fall of Adam and Eve and the murder of Abel, David and Goliath, Moses bringing water from the rock to the Israelites and the Three Magi bearing gifts to Mary and Jesus.
The center of the cross on the eastern face depicts the Last Judgment, with the saved -- led by David with a harp on Christ's right.
The damned are depicted on his left; above that is St. Paul in the desert.
These scenes appear to be connected by the themes of sin, judgment and atonement.
The western face of Muirdach's Cross focuses on the New Testament and depicts, from the bottom up: the arrest or mocking of Christ, doubting Thomas with another figure, perhaps St. John the Evangelist, who recorded the story, Christ giving the keys of heaven to St. Peter and a book to St. Paul and Moses praying with Aaron and Hur.
In the central Crucifixion scene on the western face, Christ is depicted as clothed and without pain, flanked by two soldiers.
The scene depicts the spear bearer who pierces his left side and another holding a cane with a cup, apparently representing the sponge bearer.
Between the soldiers and Christ's knees are two heads, perhaps indicating the two thieves.
The bird under Christ's feet may represent the phoenix, a symbol of resurrection.
On the right arm of the cross is a depiction of the Resurrection of Christ, with guards kneeling on each side of the tomb and three angels behind them holding a small figure representing the soul.
Monasterboice's round tower is over 110 feet tall and was divided into four or more stories inside, connected with ladders.
As with other round towers, this was used as a belfry, watch-tower, and a refuge for monks and valuables during times of Viking attack.
Records indicate that the interior went up in flames in 1097, destroying many valuable manuscripts and other treasures.
The tower is currently closed to the public.