IMG_20190717_081406 Wooden bridge or sewer segment
20190710_143822 A sculpture of Patrimpas in the Samogitian sanctuary
Samogitian Alka, or Samogitian sanctuary ("Žemaičių Alka") is a little pagan sanctuary in Lithuania, on the coast of the Baltic sea, north of the Šventoji town. It's situated on the small hill by the beach, on the other side of the dunes. You can see the sea from here, which, I suppose, makes it a perfect place for pagan rituals.
It consists of about a dozen wooden poles, which are statues of various ancient Baltic gods, carved by Lithuanian folk artists in the late 20th century.
This is a sculpture of Patrimpas, an ancient Baltic pagan god of rivers, springs, of spring, crops, peace, fertility and abundance. That's a lot of responsibility for one god, especially considering that some other Baltic gods had much narrower purposes, such as Austėja, the goddess of bees.
The snake carved into the pole is probably a grass snake, called žaltys in Lithuanian. According to some sources, grass snakes, or snakes in general, were Patrimpas' animals. Grass snakes were in any case considered sacred by Lithuanians; they were worshipped and given milk.
As with the rest of the poles, the shape of this one, too, was probably dictated by the artists' imagination more than anything else. There is way too little historical knowledge about ancient polytheistic Baltic religions to be able to tell how any deity used to be portrayed. Any mentions of Baltic deities in the Middle Ages were made by Christian monks, scribes and politicians -- people who didn't hold pagan religions in high regard. So we can only guess how those deities were visually represented (if at all) back in the day.