Ito City is famous for it's hotsprings (onsen) and great sea food. The lava outflow from Omuro-yama created a strikingly beautiful sea coast with cliffs and a waterfall. A hanging bridge is part of a hiking trail that runs along the cost here.
If you are traveling to either Hiroshima or Osaka, make it a point to drop off at Himeji to see the wonderful Himeji Castle. If you don't, you will pass through Himeji, see this marvelous fuedal structure in the distance and wonder for the rest of your life why you didn't.