Why not other beaches in France (assuming there were less fortified or more advantageous beaches in which to land in France) or beaches in other countries for that matter? As far as I know, the Germans guarded almost the entire European coastline against an allied invasion, but did the Germans fortify (with pillboxes, metal tripods, barbed wires, etc.) the entire coastline? It always struck me as odd how many soldiers so easily lost their lives during the initial waves of the invasion. Obviously, it was a success, but in hindsight, was it the best choice?
It was actually the smart move to do. It was within the allies' air coverage and less fortified, relatively speaking, then the obvious other choice Pas De Calais, shortest distance between the UK and France. They chose France because they wanted gain back their major ally, although free France which was mainly the French colonies were aiding them. I'm honestly not sure if Germany had fortified all of the viable French coastline, but it would make sense to have a majority covered by those fortifications or by Uboats and airforce.
Source: http://www.army.mil/d-day/beaches.html
I'd like to note that the allies have at this point invaded Italy so they were working their way up there.
The Normandy invasion beaches were a pretty good place to attack.
The heavy casualties (circa 10,000 casualties, 2,500 of which were deaths, out of 156,000 Allied troops involved) on D-Day were most heavy among the airborne troops, rather than on the Beaches.
Among the Beaches, the heaviest casualties were on Omaha Beach where the 34,000 US troops took about 2,000 casualties.
Casualties on the other 4 invasion beaches were lower. There were only 197 casualties on D-Day out of the 21,000 US troops who assaulted Utah Beach. The 25,000 British troops who landed on Gold Beach had 1000 casualties on D-Day. The 29,000 British troops who attacked Sword Beach took about 1000 casualties. The 30,000 Canadians who landed on Juno Beach suffered about 950 casualties.
The 13,500 airborne troops from the USA and Britain had about 3,800 casualties, (a far higher percentage than any of the units which landed on the beaches).
http://www.ddaymuseum.co.uk/d-day/d-day-and-the-battle-of-normandy-your-questions-answered