From inside the VAB: Atlantis heads for the pad.
A few hours before shuttle Endeavour touched down on the long runway at Kennedy Space Center, the great doors of the Vehicle Assembly Building (VAB) began to open. For the last time, a space shuttle was taking the long drive on the giant crawler out to the launch pad. Held firmly in place by giant clamps, the crawler moved Atlantis out of the building and along the trackway at a stately rate of less than a mile per hour. The trip would take about six hours to cover the 3.4 mile journey.
Earlier in May: Atlantis lifted up to attach to the stack.
While the media focus had rightly been on the last launch of shuttle Endeavour and the adventures of mission STS134, the shuttle Atlantis was driven to the VAB. Clamped into a giant lifting cradle, the orbiter was lifted up and oriented 90 degrees to vertical, then slowly brought to its position on the "stack"; that is the External Tank (ET) with its attached Solid Rocket Boosters (SRM's). Once all attachments were complete, systems checked, and safety tests confirmed, it was time for the rollout.
Once in place on Launch Pad 39A, the crawler disengaged from the launch platform itself and began the return trip back to the VAB area. If there are any problems or dangers, as from a hurricane, the crawler will return to the pad and bring the shuttle back. However, that is a very rare event.
The shuttle is scheduled to launch July 8th.