Maybe it's something like the French saying Le Mal du Pays

"Le Mal du Pays is usually translated as 'homesickness,' or 'melancholy. ' If you put a finer point on it, it's more like 'a groundless sadness called forth in a person's heart by a pastoral landscape"

I get the same, it's more like a contented melancholy.

Not sad, just locked into the moment, with a certain understated freedom of mind.

You're not smiling or frowing, just existing, taking it in.