You can be witness to the expansion of the new Gatun Locks when you arrive at the new Visitors Center.  There is a small entrance fee that ranges from $7-$3 dollars depending on you age and resident status. This fee will give you full access to the facilities, including a hiking path.  If you opt not to pay the fee, you may visit the center’s restaurant and enjoy the view from there.  

http://www.miamiherald.com/2013/04/07/3329175/new-locks-for-panama-canal-near.html