Taking the First Steps No one really knows who came up with the idea of stairs. Historians suspect the earliest staircases were to take people down into mines. In 2005 Europe’s oldest wooden staircase was discovered in Hallstatt Austria estimated to be more than 3 500 years old. The staircase is about four-ft wide (1.2 meters) and made from pine and spruce. The reason it didn’t decay was because of its location: a salt mine! The microorganisms (living organisms such as a bacteria fungi or viruses too small to be seen with the eye but visible under a microscope) that make wood rot can’t survive in salt mines. Ironically now that it’s been discovered it’s beginning to crumble.