The four star rather than five star rating is really down to one factor - an incredibly hard bed and single thin pillow. Other than that, the service and location are excellent, with lots of those thoughtful touches that make a hotel stand out.
Located on a quiet street close to the city centre, we were warmly greeted, and full marks to the staff for allowing my husband, who speaks decent German, to do so, rather than automatically switching to English as so many hotel staff are wont to do. We we too early to check in but were able to leave our bags, which had then been delivered to our room when we came back later that afternoon. The room was right at the top in the roof and rather sparsely furnished, but with a good coffee machine and complimentary bottled water, which was replaced each day. I would prefer a bath to a shower personally, and found the towels a bit thin and scratchy, but there were cosy bathrobes to make up. From other reviews, it sounds like the rooms to go for if you can are the ones in the annex rather than the main building.
We also got given a "mobility card" which provides free use of all Basel city public transport, very useful given how expensive the place is (you leave every restaurant in Switzerland feeling vaguely like you've just been robbed). This place is reasonable value for money by Swiss standards, especially as it includes a decent continental breakfast.
Staff were uniformly helpful and welcoming, even down to the chef who pointed me downstairs to the loo when he spied me from the kitchen window looking lost by the bar.
