Seto Inland Sea
Many of Japan's largest cities border the Inland Sea, and the countless small islands in the Sea are perfect for off-the-beaten-track exploration.
Boats are the natural way to travel around the sea. There are countless services, most running only short distances; check under your destination of interest for details.
After billions of dollars in construction works, the Seto Inland Sea is now crossed by no less than three stupendously huge bridges. From east to west: