Here are a few photos I took from a visit to the Leicestershire Regimental Museum. There are two Russian cannon outside both taken from Sevastopol during the Crimean War. As you can see they have slightly different carriages (one with four wheels, the other two). They both seem to be the same calibre guns, although I'm not sure what poundage they may be. There's what appears to be a slightly faded armourer's mark on both. I can't tell what they mean and the inscriptions are quite weather-worn. There were the initials 'M.A' on the rear of each. Apparently the guns were not definitely taken by the Leicestershire regiment during the siege, but the city had 'claimed' them for display at some point (I've seen four smaller guns in Nottingham which I assume were appropriated in the same manner). The Sevastopol wooden eagle, also pictured, was actually taken during the siege. As attested to by the inscription.
If anyone has any further info on the cannons I'd be interested to hear about it!