The castra of Bumbești-Jiu now known as Vârtop was a fort in the Roman province of Dacia.

[1] It is located 35 m west of the Târgu Jiu - Petroșani road, in Bumbești-Jiu (Romania).

It defended and secured the entrance to the Jiului gorge and the Roman road from Bumbești through Porceni over the mountains, through the Vâlcan Pass to Sarmisegetuza.

Traces of a vicus (civilian settlement) were found nearby.

It seems that this fort ceased to be used as soon as the Castra of Bumbești-Jiu - Gară was built 800 m to the south.