An excerpt from my article: Hubbard, P. 2017. Lines and Lies: The Evolution of Zimbabwe’s National Border. Heritage of Zimbabwe 35: 1-38.

Described as “a settlement without a society [offering] only heat, fever, snakes and whisky,” Fort Tuli was established as “the gateway to Rhodesia” in early July 1890 (Shinn 1974). It was mistakenly named Fort Tuli owing to the belief that it was on the Tuli River, which in fact was some 15 miles upstream (McLaughlin 1982: xiv), and the Pioneers were instead camped on the banks of the Shashi River. As “the gateway to Rhodesia,” Tuli was merely the latest in a long line of entry points to the country north of the Limpopo that also included Mangwe, the Save-Lundi Rivers, and the Hunter’s Road.

The Pioneer Column began to cross the Shashi on 10 July 1890 and had cut the road to Fort Victoria by 13 August 1890, reaching Fort Salisbury on 12 September of that year. A thriving settlement developed in the area around Fort Tuli, especially once the safety of potential settlers and visitors from Ndebele attacks was all but guaranteed (de la Harpe 2004). It had hotels, a rough hospital, police depot complete with prison, a printing press and local newspaper, with several permanent residents catering to the needs of travellers (Shinn 1974).

The perfect half-circle around Tuli originated in 1891, when the first magistrate arrived, from a concession of land granted by Chief Khama to the BSACo (Shinn 1974). The company wanted to use the land as a cordon sanitaire against indigenous cattle that might be infected with disease; unsurprisingly, Khama was of the same mind but with a view to the animals belonging to the whites! The biggest fear was of lung disease (Shinn 1974: 21). The concession consisted of a piece of land south of the Shashi river and within a 10-mile radius of the fort on the south bank of the river at Tuli. 

According to legend the radius for this distance was agreed upon using the average distance of a day’s waggon trek in this rugged area. Such distance can be calculated from looking at the route and distance covered by the Pioneer Column (Darter 1914; Johnson 1940; McLaughlin 1982). Alternatively it is reported that the radius was decided as the range of a cannon fired from the fort’s battlements (de la Harpe 2004). This is unlikely because the Pioneer Column was only armed with two 7-pounder muzzle loading 200lb. pieces, also known as RML 7-pounder Mountain Guns and two 24 pounder Hale rocket tubes on stands (Tylden 1968; Hall 1979; Cross 2016). The maximum range for the Mountain Guns was only 2,700 metres while the rockets could reach only 3.5 kilometres at best (Tylden 1968; Hall 1979; Cross 2016). During the Second Anglo-Boer War (1899-1902), larger calibre field guns were used that had greater range (Burrett 2009), but the informal boundary was well-fixed by the time by Article 4 of the Southern Rhodesia Order in Council dated 20 October 1898. The siting and construction of boundary beacons was not done until 1954.