Take a look at the set photos below for the India location shoot of THE DARK KNIGHT RISES (2012). If you look closely at the two photos, it seems there is a possibility that the Lazarus Pit might appear in Christopher Nolan's trilogy-ending BATMAN franchise. Does that mean we get to see more than just a mere flashback of Ra's al Ghul?
For those who doesn't know about the Lazarus Pit, here's the brief description below.
Lazarus Pits were accidentally discovered by Ra's al Ghul in an effort to cure a dying prince of the sultan he worked for. Ra's al Ghul dug a pit where he discovered the restorative chemical pools that he dubbed a Lazarus Pit for its abilities to heal those at death's door. After using the pit to save the life of the prince, a side effect of the pit's restorative abilities revealed itself as the prince went mad and killed Ra's al Ghul's wife, Sora. Blamed for his wife's murder, Ra's al Ghul was left to die, buried in the desert, but was soon rescued by his own tribe and a boy named Huwe. Afterward, he used the tribe to gain vengeance for what happened to him and proceeded to call himself the "Head of the Demon".
For more details, go to http://en.wikipedia.org/wiki/Lazarus_Pit