Hamar sits on the eastern shore of Mjosa, Norway's largest lake, and feels different from the fjord cities most visitors know. It is an inland town of flat farmland, railway lines, lake air, medieval church history, and one unmistakable Olympic building shaped like an overturned Viking ship.
The best reason to come is Domkirkeodden, where the ruins of Hamar's medieval cathedral sit under a glass shelter beside the lake. Add the Vikingskipet, the railway museum, and a summer trip on Skibladner, and Hamar becomes a strong day or overnight stop between Oslo and Lillehammer.
It is easy by train, which matters. You can leave Oslo in the morning, walk the lakefront museums, see the Olympic hall, and still have time for a swim or coffee by Koigen before heading back.