Are Hiroshima and Nagasaki still radioactive?

There is still some slight contamination left, but the level is quite low. And the first poster is exactly wrong about newer weapons. The first generation fission bombs were quite "dirty" because they were ineffecient in their chain reaction process. Newer fusion weapons are much more efficient, getting a bigger yield out of a smaller amount of material with a much smaller contamination footprint. The whole point is to destroy a city, not crap it up for centuries.