The Eastern Circuit (道東 Dōtō) covers the eastern half of the northern Japan island of Hokkaido.
The Eastern Circuit is composed of the following four subprefectures:
The most sparsely populated region in all Japan, this vast area is nearly 40,000 km² in size. While the easternmost part is largely flat, rural and filled with endless cow pastures, much of the circuit is ringed with mountains.
Kushiro, Monbetsu and Ōzora, Memanbetsu (near Abashiri) have regional airports.
Here, if anywhere in Japan, a rental car will come in handy. Train coverage is severely lacking (many lines have been terminated due to a lack of customers) and buses are infrequent, inconvenient and expensive.
Eastern Hokkaido has beautiful coastline, wonderful outdoor hot springs, and remote hiking. Some combination of these should make for a satisfying visit.
Hokkaido on the whole is good for seafood — if you're on the coast — and dairy, and the east is no exception. In central Hokkaido, near Asahikawa and Furano, there are a plethora of melon stands, though by foreign standards, Japanese melons are exceedingly expensive.