The castle complex is of particular archaeological importance. From excavations it can be concluded that here - as well as on the neighboring Petersberg - there was already a Bronze Age settlement. A necklace from the Middle Bronze Age (16th century BC) found in the 1990s, which must have belonged to a noble lady, suggests that the Rachelburg already had a kind of ruling function at that time.
Ober-Falkenstein Castle is said to have been built by Bishop Albuin von Brixen and the Aribones. The complex was the eponymous seat of the Counts of Falkenstein and was first mentioned indirectly in 1115, then in 1166 as "urbs", in 1188 as "castrum", and in 1287 as "burg". When 1166 is mentioned in the Codex Falkensteinensis, it is also shown in a schematic drawing. The masonry that has been preserved is dated around 1110, coins found date from around 1120; This makes Alt-Falkenstein one of the oldest preserved stone castles in Bavaria.