Throughout the centuries transportation has changed in many ways and this timeline is to show important inventions that helped to change transportation to what we know now.  The first inventions were very long ago and there is only some knowledge of when they were created.  The first boats and ships started to show up around 4000 B.C. and started the revolution of the trade, passenger and war ships we have now.  I believe that for land travel, even though the invention of the wheel could be considered one, I think there is a difference between the first wheel and the spoked wheels later.  The first, solid wheel, created a way for people to move heavy objects and made travel easier.  The spoked wheel centuries later started the creation of the first passenger vehicles.  Things stayed the same with slight improvements for a long time until the 1600's where technology started to boom and many different vehicles were created and transportation soared.  Once started, advances in transportation technology grew faster and faster until with the last century and a half has seen the most change. 

                                                                    Information for this Cited from:

Encyclopedia Britannica - www.britannica.com

The History of Transportation - http://inventors.about.com/library/inventors/bl_history_of_transportation.htm

Wikipedia - www.wikipedia.com