I visited many of the D-Day sites in Normandy in 2010. Very powerful moment for me to walk through the American Cemetary and see all those crosses, with the contrast of the beautiful setting. The beaches look idyllic yet they definitely weren't that day in 1944.
If you haven't had the chance to go, I highly recommend it. The history is in parts saddening and in others awe inspiring while the area itself is gorgeous.