Heinfels Castle, and the eponymous district court, were built on the territory of the Prince-Bishopric of Freising, Innichen. In 1239, Otto Welf, from the House of Welfsberg, starts calling himself ‘de Hunenvelse’ (he who comes from Heinfels). The castle was first named in 1288 and the original building hails back to the last quarter of the 13th Century, and is composed by the keep, jutting out from the highest point of the rock on which the castle is perched, the palas built to the west of the structure and the castle walls stretching out to the west. Back in the 13th century, Heinfels was transferred to the House of Görz and, in 1271, Count Meinhard II of Tyrol decided to keep it for himself, going against the agreement concerning the division of the family goods he had stipulated with his brother Albert. It was only in 1275 that Meinhard gave the castle to his brother, Albert II of Görz. Heinfels was the most important hub in County Görz in the Pustertal valley until the Görz line died out. In the past, a square tower used to rise to the east of the castle structure (today it has been incorporated into the western walls). This tower was the former residence of the Count of the castle who acted as trustee of the property. The castle chapel, dedicated to Saint Laurentius, contains remains of frescoes hailing back to the Late Roman and Gothic period, and was consecrated a second time in 1331. Around 1400, an imposing, three-story hall - a new living area- was erected to the west across the ruins of the old castle walls. It still dominates the western side of the castle structure to this very day. Still in the possession of the Görz family, the castle was fortified at the end of the 15th century with an extended wall and round corner towers.

After the Görz dynasty died out around 1500, Heinfels and the whole county went to Emperor Maximilian I. Between 1654 and 1783, the castle went to the Royal Convent in Hall, then became state property. In 1833, the castle was transferred to those 18 municipalities that resided in the former county of Heinfels. It was used to shelter the poor and homeless. Between 1880 and 1910, the castle was used as a military barracks. The market town of Sillian became the sole owner of the castle in 1936, making it into a private property.

During the 18th century the castle slowly started falling in disrepair. The ceiling of the palas collapsed in 1917; the tower ceiling followed next in 1928; the western wall of the palas crumbled to bits in 1932. From this moment on, regular redevelopment work is carried out and, since the 90s, has included securing the building stock as well as a partial restoration of individual parts of the structure to their original glory.

In 2007, the Loacker company, in agreement with the communities of Heinfels and Sillian, acquired Heinfels Castle with the intention of revitalising the site. The main objective was to make the castle accessible to the public again and to make it a centre of public life in Alta Pusteria, especially in terms of culture and tourism. The aim is a mixed public and private, gastronomic use. In order to achieve this, the first step was to carry out a sustainable, fundamental renovation of the castle as a matter of great urgency in order to prevent further decay of the castle complex and to preserve it for future generations as a castle complex that is visible from afar and filled with life.