Punjab witnessed major battles between the armies of India and Pakistan in the wars of 1965 and 1971. Since the 1990s Punjab hosted several key sites of Pakistan's nuclear program such as Kahuta. It also hosts major military bases such as at Sargodha and Rawalpindi. The peace process between India and Pakistan, which began in earnest in 2004, has helped pacify the situation. Trade and people-to-people contacts through the Wagah border are now starting to become common. Indian Sikh pilgrims visit holy sites such as Nankana Sahib.