I visited Monbetsu in Hokkaido a couple of years back, predominantly for the opportunity to see the drift ice that forms off the coast during the winter months. As part of that several-day trip, we drove from Monbetsu down the eastern coast of Hokkaido to the Notsuke Peninsula. I didn't know a great deal about the peninsula before my visit, but it ended up being one of the most memorable places I've visited in Japan.
If you're a nature lover, this place is for you. There are some amazing bird watching opportunities - we saw massive hawks and eagles basically as soon as we arrived. The surrounding bay freezes over in winter, and you'll see deer and foxes out on the ice - it's otherworldly. One of the most unique experiences though was getting to do an ice walk ourselves, and the subsequent photos that we took while out there!
Because the ice is so vast and so flat, it creates the perfect venue for some optical illusion styled photographs. We had a bunch of props including a small mug and a mikan orange, which we set up to take pictures with. If you get the angles right, you can take photos that make you look like you're standing inside a mug, or balancing on the mikan. Honestly, there are probably a whole host of other great photos you could take - the only real limitation is your imagination, but it was definitely a bit of fun!
I'd love to return to the peninsula in the summer months as the area is famous for its wildflowers, although the winter landscape is captivating in its own unique way!