This cover from South Africa depict a complete set issued in 2012 celebrating the UNESCO World Heritage Site
Vredefort Dome. The Vredefort crater is the largest verified impact crater on Earth. It was 160–300 km across when it was formed; what remains of it is in the present-day Free State province of South Africa. It is named after the town of Vredefort, which is near its centre. Although the crater itself has long since been eroded away, the remaining geological structures at its centre are known as the Vredefort Dome or Vredefort impact structure. The crater is calculated to be 2.023 billion years old, with impact being in the Paleoproterozoic Era. It is the second-oldest known crater on Earth, after Yarrabubba crater. In 2005, the Vredefort Dome was added to the list of UNESCO World Heritage Sites for its geologic interest.
