How to bring clothes when traveling to the four Nordic countries (Denmark, Norway, Finland, Sweden) on August 10

Wear long clothes and long trousers, preferably a rainproof jacket or the like, the kind called soft shell in Northern Europe.

Traveling shoes will suffice, of course waterproof ones are best.

Basically, a shirt with a jacket on top and trousers on the bottom. Of course, you can wear pants if you are not afraid of the cold. Sometimes it can be very hot during the day on a sunny day.

Sunglasses are a must, as the Nordic sun is harsh.