Urban planning can make a huge difference to how people live and how visitors experience the city. Streets set in squares or rectangles, for example, are easier for visitors to […]
The helicopter was invented by the Chinese in the 4th century, more than a 1,000 years before Leonardo da Vinci. It was called the Bamboo Dragonfly and could fly 25 feet (7.6 m) up and down. The first modern helicopter was invented by the French.