Hi Amin and welcome to GoY. Is that just one huge climber and where do you live?

I think it's Ivy

Looks like ivy, which when mature will flower as in the photo, mature ivy leaves lose the more recognisable palmate shape which confuses some people.

I thought ivy too but you would have expected the palmate leaves nearer the bottom wouldn't you? If you enlarge the photo as much as you can the leaves appear to have slightly pointy edges a bit like holly - never seen ivy like that before. With ivy you usually get the flowers on longer stems that stand above the younger leaves, and the leaves on the flowering stems are fresh and lighter green.
Not saying it isn't ivy but its unusual if it is.

Definitely ivy in its mature state. Cuttings taken from the mature parts will always look like this, and won't show the typical ivy-shaped leaves. The flowers are a great nectar source for insects through the winter.

Well it might be ivy, but frankly, its hard to be 100% sure - even with magnification, its hard to say because the pic's then a bit blurry. Can you post another photograph taken closer, so we can see the leaves better please.

Glad somebody else share my hesitation!

Hi, I think this may be Hedera helix arborescens, it's a non climbing species, and a very good specimen, Derek.

That will explain the leaves then.