Fort Durnford is of strategic significance due to fact that it was built on the site where Voortrekker leader Gert Maritz made his camp in 1838. While Maritz decided to set up camp on a horseshoe bend in the Bushman's river, the British built Fort Durnford on the crest of the hill. Serving as an excellent lookout point, the fort provide decent views of both the Great and Little Bushman's rivers, their confluence and Estcourt itself.

Some of the most crucial moments in South African history, occured in the Escourt area. The first Europeans to settle the region were the Voortrekkers who crossed over the Drakensberg in 1838. Without heeding the advice of their leader, Piet Retief, the Voortrekkers decided not to stay together, and soon scattered southwards to the Tugela and its tributaries, where they were involved in a series of bloody conflicts with the local Zulus. On 16 December 1838 the "Wenkommando", under the command of the Boer General A.W.J. Pretorius, defeated the Zulus at Blood River. Even though the Zulus were crushed, the settlers were still regularly disrupted by raids carried out by Bushmen and marauding Zulu dissidents. In 1847 a detachment of the British 45th Regiment from Fort Napier in Pietermaritzburg was sent to protect the settlers from Bushmen raids.

Initial reconnaissance of the area resulted in virtually the same site as Gert Maritz's camp, Saailaer being chosen. A flat topped hill across the Busman's River from Saailaer was chosen, and from this site, the troops were able to survey the area which surrounded it, especially two drifts which were used frequently by marauding parties. The first fort was originally called called the "Ordnance Reserve", and was constructed of various rough earth walls, and served mainly as a defence against the Bushmen. After the treats of the Langalibalele Rebellion of 1873, this stronghold was no longer thought of as temporary, and in 1875 a more solid fort was constructed of local sandstone, on the same site. The second fort built, a sturdy rectangular sandstone structure, which still stands today features walls more than half a meter thick and bout nine meters high. There are two square towers, situated in the south east and the north west of the fort. There are heavily barred windows throughout and numerous loopholes. The windows were originally fitted with heavy iron shutters turning on hinges spiked to the walls for closure when not manned. The municipality of Estcourt has restored the fort to an excellent condition, and the fort was proclaimed a historical monument in 1970.

Today the fort houses the Estcourt Museum, and what served as a stronhold against the Zulus, is now a seat of cultural interest, and features various displays of Military history, fossils, bird eggs,as well as exibits on the Moorleigh mission station and the Amangwe homestead. Fort Durnford is open daily from 09:00-12:00 and 13:00-16:00.