 Thomas Harrison ( 7 August ( baptised ) 1744 – 29 March 1829 ) was an English architect and bridge engineer who trained in Rome , where he studied classical architecture . Returning to England , he won the competition in 1782 for the design of Skerton Bridge in Lancaster . After moving to Lancaster he worked on local buildings , received commissions for further bridges , and designed country houses in Scotland . In 1786 Harrison was asked to design new buildings within the grounds of Lancaster and Chester castles , projects that occupied him , together with other works , until 1815 . On both sites he created accommodation for prisoners , law courts , and a shire hall , while working on various other public buildings , gentlemen 's clubs , churches , houses , and monuments elsewhere . His final major commission was for the design of Grosvenor Bridge in Chester . 
