The second “engineering feat” I have explored in my project and this blog is NOT a building. It is a road – or actually – a pass that I travel almost every weekday morning on my way to and back from school, and have for almost ten years: Munro Drive.
Munro Drive is a short pass that connects Upper Houghton and Yeoville with Lower Houghton or Houghton Estate. The low, rocky ridge that separates downtown Johannesburg from the northern suburbs is called Linksfield Ridge and Munro Drive is one of three passes that were first built to give residents of a growing Johannesburg City, access to new places to live to the north. The other two passes are Stewarts Drive and Sylvia’s Pass.
The history of Munro Drive: Munro Drive was named after John Munro, a director of The Johannesburg Consolidated Investment Company (JCI) and was initially built from stacked stone in 1919. The Munro Drive pass has been declared a National Heritage Area. It is believed that the stone walls along Munro Drive were built by Italian Prisoners of War captured during the Second World War, although I cannot find any proof of this. Munro Drive is one of only a few passes in South Africa that is under 1km long. On 1st February 1938, part of a retaining wall in Munro Drive collapsed and the road had to be rebuilt (theheritageportal.co.za).
Picture 1: An old postcard picture of Munro Drive
Picture 2 : Part of the wall collapses Source theheritageportal.co.za
My journey driving down Munro Drive: Since I have my learner’s license, I thought I would explain the pass by driving down it myself. My passenger kindly took photographs. Where Elm street intersects with St Patrick’s Road at the circle is the Southern Start of Munro Drive pass. The road starts at an altitude of 1768m and heads north as you drive down the pass. The first 130m is fairly flat till the intersection with St Pauls Road. From there it drops quickly down to a sharp left hand bend. On this corner there is a widening of the road where cars coming up Munro Drive can pull over to stop and look out over the view of Houghton and the golf course. This space is not suitable for descending traffic to stop at. The view is great, although it is disappointing that someone has sprayed graffiti on the walls here. The road then heads west for 40m then enters a full and very, VERY sharp 180 degree hairpin bend. You cannot go faster than 30 kph here or you will be in trouble.
Picture 3 : Graffiti on the wall at the lookout on Munro Drive
Picture 4 : The view from the lookout over Houghton
Picture 5 : An example of the stone clad walls along the pass
Picture 6 : Approaching the hairpin bend on Munro Drive
Picture 7: Driving South down Munro Drive
Picture 8 : Driving through the hairpin bend at less than 30kph
After the hairpin bend, the gradient steepens out to 1:7 and descends at that gradient to the 500m (past halfway) point and then the slope levels out to a more gentle 1:3. The pass ends after 900m at a T-junction with Houghton Drive at an altitude of 1727m.
Driving up Munro Drive each morning trying to get to school on time is a problem because the cars form a long line through the whole pass and there is no way to pass anyone.
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