+1 to that, the Wallace Collection is incredible - I think it's one of those things in London that not nearly enough people know about.

It's also got an interesting history: "Bequeathed to the nation by the widow of the illegitimate son of the 4th Marquess of Hertford in 1897 on the condition that no object should ever leave the collection, even for loan exhibitions." - from my write-up on https://www.niche-museums.com/36