Glastonbury Tor, Hill with church tower in Glastonbury, Somerset, England

Glastonbury Tor is a 158-meter hill in Glastonbury, England, crowned by a stone tower at its summit. Seven deep terraces spiral around its slopes leading up to St Michael's Tower, which stands as the sole remnant of a medieval church.

In 1191, monks from Glastonbury Abbey claimed they discovered the graves of King Arthur and Queen Guinevere on the grounds. The current tower was built in the 14th century after an earthquake destroyed an earlier church.

The tower is dedicated to St Michael, and the hill's Welsh name, Ynys Wydrin, means 'Isle of Glass'. A annual fair, the Tor Fair, was held here in the Middle Ages. The summit is linked in Celtic myth to Gwynn fab Nudd and to Annwn, the land of the fairies.

A steep path leads from the base of the hill up to the tower, with benches placed for rest along the way. The climb takes around 20 to 30 minutes and the ground can become slippery after rain, so sturdy footwear is recommended.

The seven terraces on the slopes have never been explained: they are as deep on the shaded north side as on the sunny south, and no other slope of the hill was terraced. Nicholas Mann argued this rules out medieval ploughing, and no bank-and-ditch rampart has been found.