Tree with pink hanging flower clusters?

[Needtosoundoffandbreathe]

Just gone past a tree on a railway embankment with flower clusters like inverted chestnut candles, so hanging down. It could be a huge shrub. Does anyone have any ideas what it could be? I have googled but couldn't see anything that looked like it.

Was it wisteria?

Buddleia?

I bet it's a buddleia. Railways tracks are lined with them.

There's a red horse chestnut tree

The flowers were drooped down, not like buddleia at all, but perhaps there's a variety like that?

Horse chestnut flowers spike upwards, these hung down.

I've only seen lilac or white wisteria.

Could it be a chitalpa? They are occasionally planted as street trees.

Could it have been a leycesteria? Their flowers hang down in spikes. It’s a shrub rather than a tree, though, and doesn’t get enormously big - couple of metres-ish?

One of the varieties of Weigela, perhaps? Not really trees, but can get quite big and some varieties have pendulous red flowers, sort of.

Robinia Rouge Cardinal possibly

Robinia / pink false acacia?

like this

Not a weigela or leycesteria, I'd have recognised those. I do think it was probably a robinia - potentially Robinia Pseudoacacia 'Casque Rouge' by the colour of the flowers. Thanks everyone!