Trip to Holland. Middachten Castle. White flowered shrub

It doesn't look like a hydrangea.
Unusual!

We reckoned it was a Hydrangea by the leaves, but it might not be.

And all that lovely blue groundcover. This bush really has some presence.

Another hydrangea...mmmmMMM!...

Looks like a hydrangea paniculata 'Pee Gee' . One of the few that blooms on new growth, instead of last years growth.

Cut them back to ground level in the spring, and stand back!! lol.