The ruin of Valkenburg castle. From overgrown heap of stones to consolidated ruin

In the introduction the unique character of Valkenburg castle is pointed out in comparison with other castles and ruins in the Netherlands. As it is an elevated castle (rare for the Netherlands) it does not fit in with the typo-chronological outline of H.L. Janssen. Because of the complicated building history of Valkenburg castle with its numerous building periods, it takes up a special place in Dutch building and architectural history. A consolidation campaign in progress at the moment offered a good opportunity to pay renewed attention to the large changes the ruin went through during the past 150 years. The consolidation periods will be investigated, the accompanying restoration ethics and the building-historical and archaeological research – which, for that matter, will not be discussed as regards content. The castle, built around 1115, was repeatedly destroyed and subsequently built up again; for the last time shortly after 1644, until finally in 1672 the definitive end came when the troops of the States General destroyed the complex almost completely. For two centuries it remained a desolate heap of rubble. The rise of tourism, as well as the growing interest in preservation of monuments and historic buildings resulted in an increasing number of visitors and for the first time consolidation, or even restoration were considered. However, reconstruction proved to be unfeasible due to lack of funds. From 1900 onwards the local VVV (Tourist Information Office) stimulated the opening and exploitation of the ruin; after 1924 this task was taken over by the ‘Stichting Kasteel van Valkenburg’. From 1920 onwards a lengthy consolidation procedure followed under the direction of the architect W. Sprenger; first a huge amount of rubble had to be cleared, followed by restoration of the surviving walls. From 1935 until after the war excavations also took place, in which several older building periods were brought to light. In the fifties for the first time stratigraphic research was also carried out at the inner courtyard. After 1972 a second restoration period followed in which the polygonal towers uncovered much earlier were consolidated. In connection with this an extensive archaeological research was carried out at the inner courtyard with surprising results. The oldest phase – a rectangular tower destroyed in 1122 – was discovered during this research. At the moment (2010) a third consolidation phase is in progress, notably aimed at technical restoration. Research plays a minor part in this