The 172 was an unusual bus route within Dublin Bus. It started in 1998 and in 1999 was rebranded Museumlink. This was because it started in Kildare Street at the National Museum and National Library, and then went via Merrion Square (National Gallery) and the Quays before serving Collins Barracks (National Museum) and terminating at Dunard Estate. As Museumlink it was operated by minibuses. When the branding was dropped it became RV operated and RV 448 was to feature predominately in the routes final years. RV 448 was for a time the oldest RV in service and therefore the oldest bus with the roller-blind destinations. However, due to the routes infrequent timetable and low passenger numbers it was withdrawn in 2009 and the residents of Dunard were directed to the 37 which served the 172 terminus.
I never did a full trip on the 172. In 2009 I travelled from Kildare Street to Wellington Quay on RV 639.