Tumulus of Trou de Billemont, Ancient burial mound in Antoing, Belgium.

The Tumulus of Trou de Billemont is a large earthen mound that rises from the landscape of Antoing and dates to the first or second century. It spans about 23 meters across and reaches about 9 meters high, with a stone drum foundation and a T-shaped internal corridor that leads to a burial chamber with small niches.

The mound was built during the first two centuries after Christ as a burial site for a member of the Roman elite. Archaeological work in 1624 and 1640 revealed its internal structure and documented the distinctive T-shaped design.

The mound was explored as early as the 17th century: digs took place in 1624 and 1640, and the scholar Jean-Jacques Chifflet took part in the second. A sketch of the interior from his work is kept at the municipal library of Besançon, and the monument appears on the Ferraris map drawn between 1770 and 1778.

The mound stands in a flat grassy field northeast of Antoing, reached on foot; no visitor facilities or panels are recorded at the site. The 9-metre slopes are steep and the grass matted, so wear sturdy footwear and take care after rain. The corridor and chamber lie under a concrete platform installed during the restoration begun in 1978.

The mound is the only large tumulus in Belgium combining a stone drum, a corridor and a chamber with niches. Its T-shaped plan was recorded in a sketch by scholar Jean-Jacques Chifflet after the 1640 dig; that drawing is kept in the municipal library of Besançon.