Medieval Castle ruin Neuburg

Neuburg castle ruin rises above the village of Mammern in the canton of Thurgau, on the Swiss shore of Lake Constance. Regional sources describe it as the largest and best-preserved castle complex on the southern shore of the Untersee, the lower arm of the lake. For anyone interested in medieval fortifications, it is a rewarding stop in the area.

Where is Neuburg?

The ruin stands above the village of Mammern, on the southern side of the Untersee in north-eastern Switzerland, at roughly 47.648° N, 8.94° E. The surrounding Thurgau-Bodensee region is known for gentle hills, orchards and lake views.

What is the history of the castle?

Mammern first appears in records in 909 as Manburron, when it was acquired by the Abbey of St. Gallen. According to available accounts, the abbey ruled over Mammern and Neuburg until the 12th century.

In 1319 the lords of Kastell near Tägerwilen received the lordship of Mammern as a fief from the monastery of St. Gallen. They also owned Neuburg above the village. Ownership continued to change over the following centuries. In the 17th century the brothers Johann Peter and Karl Emmanuel von Roll built a new castle in Mammern, which became the property of Rheinau monastery in 1687. Sources give slightly different dates for this work (one mentions 1621), so treat them as approximate.

In 1866 Dr. Freuler bought that later castle and opened a private clinic in it. A successor institution still operates in Mammern today.

What can you see today?

The medieval walls of Neuburg are a ruin, yet they are preserved well enough to be regarded as the most important site of their kind on the Untersee. Conservation work on the ruin was carried out in 2001–2003 and documented in 2004 in the journal of the Swiss castle association.

Frequently asked questions

Where is Neuburg castle? Above the village of Mammern, in the canton of Thurgau, on the southern shore of the Untersee in Switzerland.

Is Neuburg a ruin? Yes, it is a medieval castle ruin, considered the best preserved on this stretch of the lake shore.

Who owned the castle? First the Abbey of St. Gallen; from 1319 the lords of Kastell held the lordship of Mammern, including Neuburg, as a fief.

Was the ruin restored? Yes, conservation work took place in 2001–2003.

What is the castle in Mammern village itself? It is the later castle built by the von Roll brothers, home to a private clinic since 1866. It should not be confused with the medieval Neuburg.