you don't say hoW pink. If it's a deep reddish pink then it'll be oe of the varieties listed by palustris.
If it's more of a hint of pink or pink flushed than you've got a standard hawthorn,but it's flowering pink this year. I

I don't know why they do it but the hawthorns round our way some years are virtually all dead white & some years (like now) many of them are this pretty flushed pink colour.

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Jane