Grass snakes (natrix) are harmless, non-venomous snakes that can be seen en masse in the spring. Since snakes are cold-blooded, they can be found in warm, sunny places. When checking the surroundings, snakes often stick out their tongue to catch smells. Also, grass snakes are good swimmers and you can watch them in the water, so they have other name - water snakes.
All photos by Evgenia Sevryukova (@macro-jane)