South Africa's first complete dinosaur fossil was excavated in the area and dinosaur discoveries take place from time to time.

Fossilised bones and primitive stone artifacts attest to the area having been inhabited more than half a million years ago. An increasing variety of remains such as middens, burials, preserved seeds and the like suggest a continuous human presence.

In less distant times, mummified bodies and skeletons of San ("Bushmen") people, who were hunter-gatherers, as well as tools, pottery and rock painting have been found, especially in caves in the mountains. The age of some of these, places the San in the region at least 5 000 years BCE.

Later came the Khoekhoen ("Hottentot") peoples, who were pastoralists, and, more recently still, black (Xhosa) and white (Afrikaner and British) migrants. Remains of kraals, forts and trekboer artifacts may be found scattered all over. At one time or another, each of the aforementioned population groups has been in conflict with every one of the others, in which the San came off worst of all, entirely vanishing from the area.

In 1814 a number of farms were allocated to Afrikaner and British settlers in the lower Sundays River valley.

In 1877, an auctioneer from Port Elizabeth, a James Kirkwood, bought one of these farms and formed a company with the idea of irrigating the valley and making it a centre of agriculture. After years of effort, however, the company failed and the project was abandoned. Early the following century, however, his dream was realised. The town, named after him, was founded on his old farm, a successful irrigation scheme was begun and the area has become one of South Africa's major citrus producers.

The village of Colchester lies tucked between the coastal dunes, believed to be over 6 000 years old, and the river. In the middle of the 19th century consideration was given to creating a port and town there but the plans came to nothing and Colchester escaped "development".

As farming activities in the lower Sundays River intensified, the Addo farmers came into conflict with the local elephants which were very destructive of their crops. Eventually, a professional hunter was engaged to exterminate them. In 1931 there were only eleven elephants remaining when, fortunately, the government stepped in and created a sanctuary.

To-day, this park now known as the Addo Elephant National Park, has grown to some 125 000 hectares and is well on the way to becoming much larger still - about 400 000 hectares. The elephant herd now numbers over 400, a tribute to the long-term efforts of conservation. Botanically, Addo contains five of the country's seven biomes.