Today’s Wonder of the Day was inspired by angie. angie Wonders, “how many steps in a flight of stairs?” Thanks for WONDERing with us, angie!

Have you ever taken an elevator to the top floor of a tall building? Maybe you’ve ridden an escalator in an airport or shopping mall. Before these inventions, how did people get up and down? Stairs, of course! Let’s take a closer look at this invention…one step at a time.

A flight of stairs—also called a stairway, staircase, stairwell, or just stairs—does the simple job of dividing a large vertical gap into smaller vertical gaps called steps. Without stairways, we’d have a hard time climbing to the tops of buildings…or buildings would be a lot shorter!

Stairways can take many forms. They can be straight or round. They can also consist of multiple straight pieces positioned at angles and connected by small landings.

Stairways are made up of individual steps. Each step has a tread and a riser. The tread is the flat part that you step on. The riser is the vertical (up and down) part between each tread in the stairway.

Have you ever heard of a “flight” of stairs? This term is defined as an uninterrupted series of steps. This can mean the set of stairs between floors or those between landings. There’s really no set rule for what can be called a flight of stairs.

How many stairs are there in one flight? It can vary widely. It depends upon how much space there is between floors in the building. The next time you climb a flight of stairs, count them. For example, how many steps are in the flights in your school? You may be surprised to learn that the number of stairs in a flight can even vary within the same building!

Why is it called a “flight” of stairs, anyway? “Flight” is likely a metaphor for a journey upward—only using the feet instead of wings! The next time you run up a flight of stairs, think of yourself as “flying” up them.

Elevators and escalators are very convenient. But many people still take the stairs. Why? It’s great exercise! If you can, choosing to take the stairs is often a good choice for your health.

Do you often choose the stairs over the elevator? How would you like to climb the longest flight of stairs in the world? The service stairway for the Niesenbahn railway near Spiez, Switzerland, holds the Guinness World Record for longest stairway. Its 11,674 steps stretch up for over a mile!

Standards: CCRA.L.3, CCRA.L.6, CCRA.R.1, CCRA.R.2, CCRA.R.4, CCRA.R.10, CCRA.SL.1, CCRA.W.2, CCRA.L.1, CCRA.L.2

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