The Roman bath house at Bearsden near Glasgow is a delightful site. It is both small enough and well-enough preserved to be understood. Originally attached to the Roman camp at Bearsden - long destroyed - it was built by Legio XX and primarily occuped between AD142 and AD165 by a garrison made up of cavalry from the Fourth Cohort of Gauls. An ae of Magnentius which dates to AD351 was found in 1990. This suggests that the site was not totally abandoned or, at any rate, reused in some form. The site was last excavated at the end of 2008. See full site record here.
View across the Roman baths
The cold plunge pool at Bearsden
The latrines, showing the drainage