The Dietkirchener Hof, also knwon as the ''Heimbachhaus'' is a Romanesque house built between 1170 and 1190 in Heimbachgasse on the banks of the Lahn in Niederlahnstein. The building is one of the ten oldest residential buildings in Germany. The Romanesque windows on the gabels are still preserved, inside there is a barrel vaulted cellar and a baroque spiral staircase.