Killarney National Park

Too many great pictures to choose from. One in particular with a blanket of blue bells was calling me, but as I am intrigued to find out what sort of tree these flowers were on I have chosen this one.
Anyone have any ideas. It was a tall fat tree. About 15 foot high and 15 foot wide. These flower blooms were approx 10 inches big when open and the size of a fist when closed.
Very beautiful !