I hope this isn’t out of line. As it’s not strictly to do with the Wars, rather the fallout after them, and indeed not even that.

In 1826 the Duke of Wellington travelled to St Petersburg to meet the new Tsar (Nicholas I) and to offer condolences on the death of Alexander, and in an official capacity offer British mediation on the matter of the Russians going to war with the Ottomans in defence of the Greeks. Always curious about small details I pondered where he stayed.
I have been able to find out that he was put up in a house on the Great/Grand Quay (What is now Kutusov embankment) that used to belong to Count Dmitry Gourieff (Gouriev) who had been the late Tsar’s Minister of Finance and had died in 1825.

I was wondering if it is known which house this was precisely?

Josh.