Henry Alford

On thy green marge, thou vale of Avalon,
Not for that thou art crowned with ancient towers
And shafts and clustered pillars many an one
Love I to dream away the sunny hours;
Not for that here in charmed slumber lie
The holy relics of that British king
Who was the flower of knightly chivalry,
Do I stand blest past power of uttering;—
But for that on thy cowslip-sprinkled sod
Alit of old the olive-bearing bird,
Meek messenger of purchased peace with God;
And the first hymns that Britain ever heard
Arose, the low preluding melodies
To the sweetest anthem that hath reached the skies.

Legends abound about the mysterious holy place of Glastonbury, or "Avalon". The story alluded to here is that Joseph of Arimathea (the man who allowed Jesus to be buried in his tomb) ended up in Glastonbury, where he built England's first church.

The flower of knightly chivalry of course refers to the semi-legendary King Arthur, who is said to be buried at Glastonbury.

The Abbey now stands in ruins.