Transylvania - THE FOUNDATION OF THE KARLSBURG FORTRESS n.d, MEDALS by (K. J. Hoffmann). Gold medal of 6 Ducats. The fortress, eagle above. Rev. 9 lines of text above a landscape with seven hills, castles above.Müseler –; cf. Mont. 1439 (silver)Ex. auction Fritz Rudolf Künker & London Coin Galleries 1, 30 October 2015, lot 539.AU 36.6 mm. 20.83 g. RRRR. This medal on the weight of 6 Ducats is exceedingly rare! NGC UNC Details. Obv Repaired, Cleaned