Koselig is the Norwegian adjective most commonly translated as cosy, but the translation is misleading by being too thin. Koselig describes the felt quality of a small, warm, intimate moment - a candlelit kitchen on a winter afternoon, a wood-fired sauna at the end of a long mountain day, the dim wash of light from a single lamp in a rorbu kitchen while the wind moves outside. It is the Norwegian cousin of the Danish hygge and the Swedish mys, and the three concepts overlap but are not identical.
The crucial thing is that koselig is a quality you produce rather than a state you arrive in. Norwegians take real care to make a room koselig: candles regardless of season, low lighting, soft textiles, a small specific snack offered to a guest, the considered absence of noise. Norwegian hospitality at its best - at a remote DNT hut, at a family-run hotel, at a strangers's kitchen on a long ferry crossing - is consistently aimed at producing the feeling of koselig for the people present.
For an international visitor, koselig is the quality you tend to register without having a word for it. The well-run Norwegian fjord hotel that does small, considered things - fresh waffles available at the bar all afternoon, blankets on every outdoor chair, the dimmer switch turned exactly right at six in the evening - is doing koselig deliberately. The well-run DNT mountain lodge that lights the wood stove before guests arrive and serves a thermos of coffee with the breakfast spread is doing the same thing.
Traveling in Norway with even a passing awareness of koselig as a deliberate practice rather than an accident tends to make the small details of the trip more visible. The lodges we work with are chosen partly on this - on whether the people running them care about the felt quality of an evening as much as they care about the beds and the breakfast. Most do.