Snakes in general:
Snakes look from afar like a tube or branch, which is located on the road. Only when you get closer, you realize that it is an animal. Snakes have an elongated body, limbs can not be identified. You often do not notice the injury on the roadkilled snake and the animal looks as if it is still alive. This is because when run over they suffer severe internal injuries, but outwardly often remain completely intact. Snakes can be confused only with blindworms in Austria. Blindworms are very difficult to distinguish from snakes when run over. Snakes have intergrown, immovable and transparent eyelids. Snakes have therefore always closed eyelids. However blindworms have movable eyelids. Blindworms can open and shut their eyelids. Moreover blindworms have unlike snakes ear openings.
Grass snakes in particular:
The grass snake has yellowish white to orange, crescent-shaped spots on the back of the head. The head is clearly separated from the trunk. The pupils are round.
Snakes are reptiles. All reptiles are unable to maintain their body temperature through metabolic heat at a constant level, but are dependent on external supply of heat. The warming of the body is of vital importance, since all functions are temperature dependent. Asphalt roads that become very hot in the sun are therefore particularly popular to refuel heat in reptiles. If they are only warmed briefly on the road and not yet completly heated, they can only escape slowly. Snakes are also found on bike paths. When you ride the bike and notice that the branch in front of you is a snake, actually, it is often too late. Then an avoidance maneuver is usually no longer possible.