In 1892, during alterations to a field, a large tumulus was destroyed somewhere near Panenský Týnec (9 km south–east of Louny, in North–West Bohemia). The only find to survive was a marvellous and oft–published mask fibula from the turn of the 4th century BC (illustrated for example in Filip 1969, 995, Tab. LXXXIV/1; Pleiner et al. 1978, fig. 149, tab. 66). By comparing aerial photographs with old cadastral maps and the original, very short report in the literature, it was possible after 110 years to precisely locate the site and partially reconstruct the finds situation. The tumulus, with a diameter of 30 m and a 2.5 m wide ring ditch, lay on the western edge of the village, on the summit of an extended spur offering broad views of the surrounding landscape. The inhumation burial was either at the original ground surface level or somewhat above it within the earthwork, either beneath stony rubble or in a stony cist. In neither case was there a sunken grave chamber – the original report, the aerial photograph and the geophysical measurements conducted on the site all go against this suggestion. A „Princely“ tumulus of such size must have contained a large quantity of grave goods, but these were either stolen or destroyed due to the discoverers’ lack of knowledge. Aerial prospection conducted by one of the authors in North–West Bohemia over the last decade has led to the discovery of 445 archaeological sites, of which 50 are documented tumulus relicts (actual tumulus accumulations in other areas, with the exception of the densely wooded regions of southern and western Bohemia, have almost all been ploughed out or otherwise destroyed).