No Jules, you won't need an iron and they are prohibited anyway. The Diamond does have self service laundry rooms with about 8 washers, 8 dryers and 4 or 5 ironing boards and irons. It is very convenient especially when cruising 25 days!!! Enjoy!
Teresa and Larry
#36-Carnival Splendor 9/16/12
7 night Mexican Riviera
#37-Allure of the Seas 11/11/12
7 night Eastern Caribbean
O, no iron...Princess has self service laundry rooms with irons and boards for your use along with washers and dryers, so keep the iron at home. Also, pack your good stuff in the plastic cleaner bags, shouldn't need ironing at all.