I greatly enjoyed my 5-night stay at the Clarion Hotel The Hub.
The hotel itself is beautiful, clean and well maintained. If you're someone like me who wants to be within walking distance or a short transit ride to museums, shopping districts and great restaurants, then this is a great area to stay in. Also, I'm a female solo traveler and never felt unsafe even when exploring at night.
Every interaction with any member of the staff was a positive experience, particularly when my cell phone malfunctioned and a member of their team was able to provide me with walking instructions to the nearest phone repair shop.
The breakfast is far superior to any hotel breakfast I've experienced in North America. They offer a large variety of food and drink options, including a made to order section with chefs.
I only visited the bar once during my stay but the bartender makes a great espresso martini!
If I ever find myself back in Oslo I would happily book another stay at this hotel.