GEOLOGY ON POST STAMPS

  Wodospady Czarnej Wisełki, Beskidy.
  Cascades of the Black Little Vistula, Beskidy Mts.

  Wodospady Świdra, Mazowsze.
  Cascades of the Swider River, Mazovia.

  Wodospady Tanwi, tzw. szumy, Roztocze.
  Cascades of the Tanew River called "roars",
Roztocze Upland.

  Wodogrzmoty* Mickiewicza, Tatry.
  Mickiewicz's Waterfalls, Tatra Mountains.