The telescope was invented by Hans Lippershey, which was only capable of seeing ships about 1-5 hundred yards away. Then Galileo Galilei improved the telescope by making it longer and putting more lenses in. Johannes Hevelius built the Aerial telescope by making it more than 100ft in length and had to use a crane to hold it.
Isaac Newton invented the Reflecting telescope, which only used 1-2 lenses but 2 mirrors, making it more powerful/ see father. William Herschel built a lot bigger version of the reflecting telescope, making the mirrors 49inches in length and the tube 40feet long. The Hale telescope was an even bigger version of the reflecting telescope; it was 200 inches in length.
ESO‘s VLT was a lot, lot bigger than the previous version of the reflecting telescope. This telescope boasts advanced adaptive systems, which counteract the blurring effects of the Earth’s atmosphere. Now we have 4 huge telescopes in Chili that are the most powerful telescopes in history. They are so powerful that they can see galaxies billions of light years away (that is the ESO VLT). And the best thing is that these telescopes are only a couple hundred feet apart and are near each other.
Visit http://en.wikipedia.org/wiki/History_of_the_telescope for a lot more information