You'll find lots of inspiration in Houzz photos and Pinterest. Save some to your idea boards. It looks like it will be a lovely hallway.

You just have to find a picture you like and copy it.

the tricks to making it work are: make sure the floor you choose looks the same quality as the rest of it- avoid trendy colours such as grey, avoid anything rustic. my preference would be for a patterned tile look but a dark brown (almost black) parquet style would also work. be critical of the floor you have seen- if it is very black will it look too crisp in a century old space that is no longer completely perfect?

you also need to make the most of the features you have so paint the walls and the details different colours or at least different shades. again be careful to choose a scheme that fits- a cold grey could cheapen it, a warm grey could look very expensive teamed with white. my preference is for more dramatic colour to take advantage of the proportions