Abashiri is a small city in the northeast of Hokkaido. Although there are other attractions, the major attraction is the Abashiri Prison which was used to house the worst criminals in the country. The harsh conditions of this prison as well as the extensive security measures meant that escapes were few. Although the old prison is now a museum, there is a new maximum security prison that is in use and houses Japan's worst criminals to this date.
The Mt Tento Observatory is also worth visiting. You can observe drift ice and enjoy an excellent view of the Sea of Okhotsk. Kitahama station is also close to the Sea of Okhotsk and you are able to have a cup of coffee while enjoying the view of the sea from a different angle.