The Porta Nigra was converted into a double church in the Middle Ages! From the city, there was a staircase leading up to the second floor. On the side, there was a staircase to the third floor. There was a floor over the open middle section. The gate was part of the city wall that ran around Trier and was over six kilometers long. Why was this gate not demolished, like so many buildings from Roman times? That is because in the eleventh century, a hermit, Simeon, lived in the gate as a hermit. This Simeon was later canonized. The place where he had stayed became a place of pilgrimage.

The Simeonstift is the monastery of the hermit Simeon. The museum has modern exhibition rooms in the old historical core of the building. The collection focuses on the early modern period up to the twentieth century. For example, the museum has the original medieval figures from the main market in Trier and also the original market cross from the year 958

The pillar where we are now standing with the market cross is a reminder that in 882 AD the Normans stormed Trier, the archbishop decided to move the market square from the river to its current location where the Hauptmarkt is still located today. The pillar used for the cross dates from Roman times and is an old granite column from the Cathedral. The original cross is in the city museum of Trier, Simeonstift. What immediately stands out on this central square is that the houses around the square are mostly half timbered. Half timbering is a construction method for making walls where the supporting structure consists of wooden beams. Half-timbering is a form of timber frame construction. On the market is the market cross from 958. It is a copy, the original can be seen in the Simeonstift museum.

The Dom is enormous. For a long time this church was the largest church north of the Alps. Originally the Dom was a double church; the northern part is the current Dom; the southern part is the Liebfraukirche. The Dom is the oldest episcopal church in Germany. Its core goes back to a Roman Basilica which means administrative building from the fourth century AD. The Dom was probably built on the site of the palace of Helena, the mother of Emperor Constantine. On the outside the Roman brickwork of the original rectangular basilica from the fourth century is still clearly visible.

Liebfrauenkirche one of the oldest Gothic churches in Germany. The church was built on the foundations of the old double church. It dates from the thirteenth century. The exterior is richly decorated. Especially the west façade with the portal located in it, but to be honest most of the sculptures are copies, but the heavily weathered sculpture in the tympanum above the door is still original and shows episodes from the youth of Christ.

Thermen is the Latin word for bathhouses. In all Roman cities you will find several bathhouses. For example, the city of Rome had no less than 856 around the year three hundred! Incidentally, in these types of complexes you could not only bathe, but also do sports and get massages. Trier already has three of these types of complexes. In addition to the Keizerthermen, these are: the Barbarathermen and the baths at the cattle market. The Keizerthermen are the largest bathhouses in Trier. The complex was built in the fourth century AD. It was robbed in the Middle Ages.

This house is the birthplace of Karl Marx. It is set up as a permanent museum. Marx lived in the nineteenth century. Karl Marx was a German thinker who was a founder of the labor movement and a central figure in the history of socialism and communism. He wrote Das Kapital and The Communist Manifesto, two very influential works.

The Frankenturm was built around the year 1100. It is an example of a Romanesque residential tower. This tower has nothing to do with the Frankish tribe, but is named after an inhabitant of this tower: Franco von Senheim. The construction technique is a true imitation of Roman construction. Of course, there were still many examples of this in Trier. The tower was later used as a residence for servants of the archbishop.