This June, I have been visiting my native Denmark, for the first time in seven years.
Although I didn't exactly start my interest in beach combing on these shores, Denmark is the place where I had most access to the beach, for the greatest number of years.
Sea glass is relatively uncommon in Denmark, at least in the areas where I have looked. Denmark's social policy of environmental awareness is quite old, so it has been a long time since much glass was discarded on the shores, here. In addition, most glass bottles in Denmark have had a hefty deposit for more than 50 years (when I was little, one of the ways we'd make extra money was to search the side of the road and garbage cans for empties), further discouraging the trashing of glass containers.
Most Danish sea glass is either clear, brown, or a shade of olive that has been used for beer bottles here for almost a century. What we think of as common ("Heineken") green is relatively scarce here. Seafoam is also scarce. Any other colors are extremely difficult to find.
Surprisingly, sea glass is not very common (or very nice) around Copenhagen, even though it's a major population center. Copenhagen sits on a narrow strait and the beaches are generally a very fine powdery sand (few rocks) as a result of which there is neither enough wave action or good abrading material to create nicely rounded sea glass.
All that said, I have enjoyed walking along the shores of my childhood, thinking about days gone by. As a testament to the relative scarcity of sea glass in Denmark, the picture above is all the glass I have found on three trips to the beach.