Can horses sleep standing up?
Horses can doze standing up thanks to a "stay apparatus," a system of tendons and ligaments that locks their legs in place, but they need to lie down for deep REM sleep.
How does the Panama Canal lift ships?
The Panama Canal uses locks to lift ships about 85 feet up to Gatun Lake and then lower them back down to sea level.
How many steps are in the Three Gorges Dam ship locks?
The Three Gorges Dam has a five-step ship lock.
Does the Suez Canal have locks?
The Suez Canal opened in 1869 and has no locks, because the Mediterranean and Red Sea are at nearly the same level.