Romeinse Wachttoren, Utrecht

Fletio is a possible name of a Roman border fort and army camp in the Lower Germania province of the Roman Empire. The exact location of the fort is known; at this place in the residence of De Meern there is a reconstruction of this fort, the Castellum Hoge Woerd, since 2015, whether this fort was also called Fletio is doubtful.

It was one of the forts, in Latin castella, along the northern border, the limes of the Roman Empire. The Rhine and its tributary arms formed a natural border. This river was therefore used by the Romans for the defense of their national border, the Lower Germanic Limes. The Rhine was also of great importance to the Romans for transport to the part of Britain they had also conquered. A series of border forts along the Rhine played a role in this defense. One such walled border fort was located near present-day De Meern. The relatively small fortress measured 85 by 120 meters. Immediately outside the walls there was a small settlement where people lived who provided non-military services to the Roman troops.