The kelterhaus is located on the railing of the Weilberg Roman villa on the edge of the city quarter "Ungstein".
Shortly before reaching the modern path, a staircase leads to the right. Immediately after descending the stairs, we are standing inside the once 15 m wide and 30 m long wine press house, which reached as far as the path running to the south. The facility offered sufficient space for processing the grapes and for fermentation in vats. Today, the preserved and reconstructed remains of the wine press lie protected in the wine press house on the slope. The treading basins can be seen behind the grids. Originally, as in today's reconstruction, there was only one large grape treading basin and a small must collecting basin made of sandstone. When their processing capacity was no longer sufficient, the plant was rebuilt and the capacity doubled by adding another treading basin made of used bricks on the east side. Now it was possible to fill one basin with grapes and crush the berries with one's feet - mashing and juicing, we would say today - and at the same time to bring the juiced mash from the other basin to the wine press. The wine press was probably a tree press. When they were found, the two columns that today support the roof of the protective building above the wine press lay parallel in front of the western basin. In Roman times, they were used as supports for the winepress tree. When the wine press was not in use, the wooden press log, several metres long, was placed on the consoles. During pressing, it pressed on the mash in the winepress area with the help of a winch or a Kelter stone. After the destruction or abandonment of the press house, a metal-working craft enterprise used the facility. The pillars lying on the ground were probably used for grinding metal tools. On the eastern pillar, one can still see clear traces of sharpening with iron oxide.