Unnamed -- but found out it is a banana shrub!

I saw this flower today on three trees growing at the riverwalk area.   I have just started researching to see if I can find out what it is but so far no luck.  I am thinking it is some kind of magnolia as the leaves are waxy and the flower has petals that are thick and soft like a magnolia.  It has no smell.  The blooms are only about two inches across.  

Edit -- thanks to Pipersmom for identifying this as a banana shrub.  There definitely was not a banana smell which might be because the plants were trees about 15 feet tall instead of shrubs.    But I was on the right track as this is in the magnolia family!   

I asked the ranger who was right there at the trees.   He said "I am not really the plant guy, I mostly know the birds and other animals here."   Really!!!     

If anyone knows, please let me know!