In a lengthy and emotional interview with The Associated Press in his Statehouse office, the governor described five meetings with Maria Belen Chapur over the past year, including two romantic, multi-night stays with her in New York before they met there again intending to break up.
He said he met her two other times - their first meeting in 2001 at an open-air dance spot in Uruguay and a coffee date in New York in 2004 during the Republican National Convention. He said neither time was romantic.
It was the first disclosure of any liaisons with Chapur in the United States and contradicted a public confession last week during which Sanford admitted to a total of five encounters over their eight-year relationship.
He previously announced he would reimburse the state for money spent during a government trip to Brazil and Argentina in June 2008 when he saw Chapur. He insists no public money was used for any other meetings with her.
He saw Chapur again in mid-June of this year, visiting Argentina without telling his staff he was going to be out of the country. He instead led them to believe he was hiking on the Appalachian Trail.
By the time he returned to a puzzled public, staff and family, his public image and emotional state had unraveled. He admitted the affair at a rambling press conference.
Now Sanford is attempting to salvage his personal and professional lives. He and wife Jenny, parents of four sons, say they are trying to reconcile their 20-year marriage but have not been sharing the same house for several weeks. Jenny Sanford found out about the relationship in January when she discovered a letter the governor had written to his mistress.
The governor said he met Chapur in Punta Del Este, Uruguay, in 2001 after his final term in Congress and before his first term as governor. He said the two struck up an e-mail correspondence after meeting on a dance floor - a chance encounter during which he counseled her into the night about her failing marriage.
"There was some kind of connection from the very beginning," he told The Associated Press.
For the next seven-plus years, Sanford said, the two exchanged messages, sometimes sporadically.
He took a state economic development trip to South America in 2008 and the relationship became physical, after which their e-mails reflected his anguish over what they'd done. "Now I am frightened," he told the AP, describing his state of mind at the time. "It was before safe. But now it's not safe. We gotta put the genie back in the bottle."
The two met in New York two more times in 2008: two nights in Manhattan in September and three nights in the Hamptons in November. Each time, Sanford claims he flew coach, paid for it himself, paid for the hotels in cash and told his staff he was reachable via cell phone.
In early 2009, after Jenny Sanford discovered the affair, the couple went into counseling. She has told The Associated Press that he asked her several times to visit the mistress and she refused.
But the governor claims he wanted to end the affair in person and, with his wife's permission, went to New York with a "trusted spiritual adviser" serving as chaperone. The three went to church and dinner together and parted ways the same night.
But he visited Chapur again in Argentina on June 18, one final trip that brought the whole affair to light.