▁train ▁to ▁the ▁town ▁square , ▁where ▁a ▁number ▁of ▁attra ctions ▁were ▁laid ▁on . ▁ ▁Places ▁of ▁interest ▁ ▁Much ▁of ▁the ▁att raction ▁of ▁Cast let own ▁is ▁in ▁the ▁quality ▁of ▁its ▁many ▁ 1 8 th - ▁and ▁early ▁ 1 9 th - century ▁buildings , ▁many ▁constructed ▁in ▁the ▁local ▁silver - gre y ▁lim estone . ▁The ▁town ▁centre ▁retain s ▁its ▁early ▁layout , ▁echo ing ▁the ▁cluster ▁of ▁houses ▁around ▁the ▁Castle , ▁the ▁har bour ▁and ▁the ▁military ▁para de ▁ground , ▁is ▁still ▁used ▁as ▁a ▁market ▁place . ▁The ▁interested ▁visitor ▁can ▁still ▁identify ▁the ▁original ▁building ▁plots , ▁and ▁the ▁cro ft s ▁attached ▁to ▁them , ▁which ▁have ▁given ▁their ▁name ▁to ▁a ▁resident ial ▁area ▁close ▁to ▁the ▁town ▁centre . ▁▁ ▁Castle ▁R ush en ▁is ▁a ▁medieval ▁castle ▁which ▁to wers ▁over ▁the ▁Market ▁Square ▁to ▁the ▁south - east ▁and ▁the ▁har bour ▁to ▁the ▁north - east . ▁, ▁a ▁former ▁ ▁of ▁the ▁Royal ▁Navy , ▁was ▁named ▁after ▁the ▁castle . ▁It ▁is ▁the ▁foc al ▁point ▁of ▁the ▁town ▁and ▁is ▁open ▁to ▁the ▁public ▁between ▁E aster ▁and ▁October . ▁ ▁The ▁Old ▁House ▁of ▁Ke ys ▁was ▁the ▁location ▁of ▁T yn wald , ▁the ▁Man x ▁parliament , ▁from ▁ 1 8 2 1 ▁until ▁it ▁moved ▁in ▁ 1 8 7 4 ▁to ▁Douglas . ▁The ▁house ▁was ▁renov ated ▁in ▁ 2 0 0 0