Johannesburg - Security has been beefed up and roads closed around the Wanderers Cricket Stadium in Illovo, where former US President Barack Obama will deliver the 16th Nelson Mandela Annual Lecture on Tuesday.
Mandela would have turned 100 years old on Wednesday.
At least 15 000 people have been accredited to attend the annual lecture, including prominent leaders, presidents, heads of states and African royalty.
Authorities have announced that Corlette Drive will be closed off between Ruud and Irene roads between 4 am and 11 pm, while only accredited vehicles and pedestrians will be allowed near the stadium. A contingent of metro and South African Police Service has been deployed to ensure security.
Obama, who made his first trip to Africa after his presidency, beginning in his native Kenya to launch his sister's educational foundation, will speak about renewing Mandela's legacy and promoting active citizenship in a changing world.