The 12 Biggest Breakthroughs In Transportation Technology
1 ROADS PAVE WAY FOR NEW TRANSPORTATION MODES For the earliest humans the first means of transportation was simply walking People followed paths trampled by animals Later they built roads to make travel easier The first evidence of roads built by people appeared in approximately 4000 BCE A city in what is now Iraq had streets paved with stone Other early roads were made of packed earth Travelers followed them on foot atop animals and later in vehicles pulled by animals The Roman Empire built the first major road system starting in approximately 300 BCE A typical Roman road had several layers A trench was filled with large stones These were covered with smaller stones cement and sand A top layer of smooth paving stones formed the surface of the road These well-built roads linked trade routes between Europe and Asia Modern technology has led to complex highway systems 4
Rome Italy still uses some of its ancient cobblestone roads Roads let people travel long distances more quickly and easily They could move to new places to find food or work They could trade goods between cities People also learned about 46,000 Approximate miles 74,030 km of highways in the US interstate system First used in approximately 4000 BCE in Iraq Made of stones and packed earth and later pavement Helped people travel greater distances distant places from travelers Roads connected these places and created the foundation for later forms of transportation ROADS ACROSS AMERICA The first highway to cross the United States was finished in the 1920s The Lincoln Highway went from New York City to San Francisco California In 1956 President Dwight Eisenhower signed the Federal Aid Highway Act It funded more than 40,000 miles 64,374 km of roads In time highways linked all major cities 5
2 WHEELS LEAD TO FASTER EASIER TRAVEL Soon after building the first roads people invented a better way to travel on them Ancient pictures show that the wheel was used as early as 3500 BCE in the Middle East Wooden disks were attached to carts People or animals pulled the carts to carry loads The first wheels were cut from wooden slabs In approximately 2000 BCE people started to make wheels with spokes The spokes connected the center of the wheel with the rim Spoked wheels were lighter and stronger They could be used to make lightweight horse drawn chariots At first wheels used four spokes then six or eight Wheels with more spokes were more stable and made for a smoother Spoked wooden wheels have been used for more than 4,000 years 6
ride An axle let the wheels rotate around a central pole Metal rims reduced wear on the wheel These advancements were used on wagons and chariots in the Middle East and Europe 6 Number of spokes in the wheel of an Egyptian war chariot Used as early as 3500 BCE in the Middle East Provided faster transportation Made it easier to transport large loads Used on military chariots An ancient carving shows a chariot pulled by horses EGYPTIAN CHARIOTS Soon after the invention of the wheel armies started building chariots A chariot is a two wheeled carriage that is usually pulled by horses The Egyptians made lighter stronger chariots with well-designed harnesses The chariots could be used to pursue enemies The chariots gave the Egyptians a military advantage as they expanded their empire beginning in approximately 1550 BCE 7
