▁is ▁emb ell ished ▁with ▁decor ative ▁t iles , ▁made ▁by ▁Mer cer ▁at ▁the ▁height ▁of ▁the ▁Arts ▁and ▁C raft s ▁movement . ▁The ▁castle ▁is ▁filled ▁with ▁an ▁extensive ▁collection ▁of ▁cer am ics ▁embedded ▁in ▁the ▁concrete ▁of ▁the ▁house , ▁as ▁well ▁as ▁other ▁artifact s ▁from ▁his ▁world ▁travel s , ▁including ▁c une iform ▁table ts ▁discovered ▁in ▁Mes op ot am ia ▁d ating ▁back ▁to ▁over ▁ 2 3 0 0 ▁B CE . ▁The ▁home ▁also ▁contains ▁around ▁ 1 , 0 0 0 ▁prints ▁from ▁Mer cer ' s ▁extensive ▁collection , ▁as ▁well ▁as ▁over ▁six ▁thousand ▁books , ▁almost ▁all ▁of ▁which ▁were ▁annot ated ▁by ▁Mer cer ▁himself . ▁ ▁The ▁Castle ▁was ▁listed ▁on ▁the ▁National ▁Register ▁of ▁Historic ▁Places ▁in ▁ 1 9 7 2 , ▁and ▁was ▁later ▁included ▁in ▁a ▁National ▁Historic ▁Land mark ▁District ▁along ▁with ▁the ▁Mor av ian ▁Pot tery ▁and ▁T ile ▁Works ▁and ▁the ▁Mer cer ▁Museum . ▁These ▁three ▁structures ▁are ▁the ▁only ▁pou red - in - place ▁concrete ▁structures ▁built ▁by ▁Mer cer . ▁The ▁Mor av ian ▁Pot tery ▁and ▁T ile ▁Works ▁is ▁located ▁on ▁the ▁same ▁property ▁as ▁Fon th ill ▁Castle , ▁and ▁the ▁Mer cer ▁Museum ▁is ▁located ▁about ▁a ▁mile ▁away . ▁ ▁Fon th ill ▁Castle ▁and ▁the ▁Mer cer ▁Museum ▁are ▁operated ▁by ▁the ▁Buck s ▁County ▁Historical ▁Society , ▁whereas ▁the ▁Mor av ian ▁Pot tery ▁and