The modern school was built in the Gothic Revival in 1872 by Lucas Brothers, who also built the Royal Albert Hall and Covent Garden. It was designed by architect Philip Charles Hardwick (who was also surveyor of the Great Western Railway) and is noted for its perfectly balanced asymmetry!
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Charterhouse Deo Dante Dedi Lodge was founded in 1901 and is lodge number 2885 on the register of the United Grand Lodge of England. The Lodge is composed of Old Carthusians and Masters and Officers, present and past, of Charterhouse School, Godalming, Surrey as well as Brothers and Officers of Sutton's Hospital in Charterhouse, London. The Lodge has always maintained a close link with the School in Godalming through the membership of the teaching staff and it also has a proud tradition of encouraging qualified Brothers of Sutton's Hospital to join, either in an active or an honorary capacity.