Less Than a Century
Since before Leonardo da Vinci, mankind was obsessed with taking to the skies. People came up with some pretty odd inventions to fly alongside birds, only to come crashing down to Earth and reality. But in 1902, Wilbur and Orville Wright, aka the Wright brothers, succeeded in keeping their craft airborne for 59 seconds. This was a major breakthrough in aeronautics.
Although it took over 500 years to achieve this mega feat, mankind took its first step on the moon in less than a century. We went to the moon in 1969, not 1968 but a year later (Even Stevens, anyone?).