SortStack #874 — 2028-10-30

By size · Order from shortest to longest.

1. A human red blood cell 8 µm

   Your body makes around 2 million of them every second to replace the ones that wear out after roughly 120 days.

2. A standard house brick 22.5 cm

   Fired clay bricks have been made the same basic way for over 5,000 years, outlasting the empires that baked them.

3. A one-person kayak 3.4 m

   The kayak was invented by Arctic peoples thousands of years ago, sealed with animal skin to stay watertight.

4. The Leaning Tower of Pisa 58 m

   It began tilting during construction in the 1170s because of soft ground, and engineers only stabilised it in 2001.

5. The Brooklyn Bridge (total length) 1.8 km

   When it opened in 1883, a stampede fearing collapse killed twelve people; a circus later marched elephants across to prove its strength.

6. The Kiel Canal, Germany 98 km

   The world's busiest artificial waterway, it lets ships skip the long, stormy voyage around Denmark.

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