Η Google into a cooperation with the US National Park Service offers 360 degrees through Street View for 40 National Parks and Cultural Monuments of the United States.
In addition to his virtual tours Street View, you will have access online museums exhibiting historical objects and national treasures with full description and accompanying history brochures.
Perhaps in the near future the holidays take place behind a screen and a headset. However, at present, because the air ticket to the USA is quite high, this virtual tour is the most economical solution for seeing national parks in the country. Virtual holidays just by two-three mouse clicks away.