Tongerlo Abbey, Premonstratensian monastery in Westerlo, Belgium

Tongerlo Abbey is a Premonstratensian monastery in Belgium with a church and convent buildings arranged around courtyards and linked by covered passages, showing Gothic architectural features. The site spreads across woodland grounds with gardens, water features, and open spaces that support both community life and visitor access.

Tongerlo Abbey was founded around 1133 by Abbot Waltman of St Michael's Abbey in Antwerp and the local nobleman Giselbert of Kasterlee, who donated the land and later became a lay brother. The founding charter, attributed to Bishop Burchard of Cambrai, is disputed because Burchard died in 1130. The abbey became a major Premonstratensian centre in the Campine, with rights over some forty parishes. French revolutionary forces expelled the canons in 1796 and sold the property; the order was re-established in 1838 and the abbey bought back in 1840 under Peter Hubert Evermode Backx.

The abbey's name comes from the village of Tongerlo in Westerlo. Its canons run a bookshop and bakery, and Tongerlo abbey beer is brewed for them by Brouwerij Haacht. Three canons died as Catholic martyrs: Arnold Vessem and Hendrik Bosch in 1557, Peter Janssens in 1572.

The abbey lies in Tongerlo, part of Westerlo, about 10 km east of Herentals. The gatehouse combines a 14th-century Romanesque base with a 16th-century Gothic upper storey. The 1852 neo-Gothic church by Paul Stoop stands beside the long red-brick convent range. A paved path crosses the lawn to the buildings.

The on-site museum holds a 16th-century copy of Leonardo's Last Supper that preserves original details that have faded from the painting in Milan. This version offers visitors a glimpse of what Leonardo's composition looked like when first completed, before age and restoration altered its appearance.