Former US president Bill Clinton paid former president Nelson Mandela a visit on Tuesday at his home in the Eastern Cape village of Qunu.
A statement from the Clinton Foundation said last week that Clinton would visit Qunu on Tuesday, to attend the opening of a container library at the No-Moscow Primary School.
It was unclear whether he would be attending Mandela's birthday celebrations on Wednesday.
His visit was part of a round-trip of the African continent.
Qunu was besieged by the media ahead of Mandela Day.
Close friends and family were seen being smuggled into Mandela's home by convoys of vehicles.
Photographers positioned themselves outside the entrance to the home, and attempted to follow exiting vehicles in hopes of confirming whoever had visited Mandela.
Several people thought Mandela would have attended his cousin Morris Mandela's funeral last Sunday.
Mourners were told he could not make it because of the cold winter weather.
"He is old, he could not have come to the funeral and on Sunday it was very cold," said Mzwakhe Mandela, Morris's son.
The guest list for Wednesday's lunch with Mandela has been closely guarded. Only key employees and local caterers are allowed entry into the homestead.
Inside the Mandela yard, a South African flag was seen hanging high. It is known among villagers that when the flag is up, Mandela is home and is feeling "sound and well".
Across the N2 highway from Mandela's house is the home of Silumko Mandela, a close family relative.
He said he had been bothered since last week by the media making enquiries, but was used to them.
"Look, those guys come here often, but at one time the chief in the village told us to be kind to visitors, so we are. The journalists are here to record the history of our own son, uMadiba Omhle [the great Madiba]," he said.
Silumko said he was waiting for a call from Chief Mandla Mandela, the former president's grandson, to tell him about tomorrow's proceedings.
"By now, we would usually be knowing what is happening tomorrow, but I do think Mandla has been too busy. Since his arrival, there have been number of things in the family," said Silumko.
About a kilometre from Mandela's house, events are underway at the Nelson Mandela Museum.
On Tuesday, the focus was on legacies and the state of archives in honour of Nelson Mandela.
Reverend Frank Chikane and African National Congress chairwoman Baleka Mbete were scheduled to give speeches on Tuesday morning, said museum spokeswoman Nokuzola Tetani.