Category Archives: Sahara book reviews

Rare film of Ralph Bagnold in the Libyan Desert

bagcarA few months ago the bagnolds-expeditionsBritish Film Institute released archive film of the early motor expeditions of Ralph Bagnold and his crew, exploring deep into the Libyan Desert. (Click BFI if youtube below gets deleted). The map top right shows all his expedition in the 1930s.

The film is 49 minutes long and describes the first recce in 1929 into the Great Sand Sea of the Western Desert via Ain Dalla spring. It was here that Bagnold’s group found lowering tyre pressures, as well as using sand plates and rope ladders, enabled heavy vehicles to traverse dunes.

baggpushA year later they set off towards Jebel Uweinat, a massif located by Ahmed Hassanein Bey less than a decade earlier during a camel trek from Jalo in Libya. At Ain Dalla camels brought in extra fuel, and the cars continued bagcarrto Jebel Kissu south of Uweinat, then east for the Nile via Selima oasis.

In 1932 they based themselves again at Jebel Kissu where they refuelled from Selima, then explored the Sarra Triangle (now in Libya) and northeastern Chad.

Heading south to El Fasher, they passed herds of ostrich and oryx, since shot out by rifle hunters, before heading north for Merga, back to Selima and home via Wadi Halfa.

The maps on the left and below show the routes of all these trips and Bagnold’s book, Libyan Sands (right) covering all these expeditions and more and is well worth reading. Reviewed here.


Sahara by 2WD Fat Bike

Some images and info from Cyclo Long Cours and Blida Nostalgie

fatfatIn 1986, long before the current fat-bike fashion, Jean Naud, a 55-year-old Frenchman set off to ride his three-wheeled bicycle 3200-km across the Sahara from Algiers to Timbuktu.
Brought up in Blida, just south of Algiers at the foot of the Atlas mountains, Jean Naud had made two previous cycle tours in the Sahara. One, as a 23-year-old way back in 1954, from Algiers as far as Ghardaia where he was born in 1931. And another in 1980 from Zinder in Niger, north via Agadez and across the Sahara to Tamanrasset – a distance of some 1300-km. This time he was riding a bike running prototype, low-pressure Michelin fat tyres (below left). At that time this route would have been just about all piste, but he recalls passing some Brits stuck in the sand near the Algerian border in their Peugeot 404, as he cycled silently past.

Although the Sahara isn’t all a wasteland of soft sand dunes, the thin tyres of a regular bike would easily sink or damage the rims on rocks under the required loads needed for desert travel.
I’ve met the odd cyclist in the Sahara. The big problem with off-highway pushbiking is the load needed to maintain autonomy, not least, water. On a conventional bike it’s barely possible without relying on passing traffic, because the tougher the terrain the greater your water consumption. Even in winter in the central Sahara, I’d guess you’d need five litres to cover about 60 kilometres on a sandy piste. And that would be a long day.

An automotive engineer, Jean Naud’s initial solution was to run fat tyres in 1980 in NIger. This time he added a second driven rear wheel to improve traction and aid flotation at pressures as low as 7psi. He then went one step further and devised a hefty hinged subframe (above right) which could both raise and disengage drive from the middle wheel to reduce the drag and pedalling effort on firmer surfaces, or when running lighter loads. Mechanically, disengaging axles (as well as hubs) was commonly done on pre-electronic 4x4s in the 1980s, for the same energy-saving reasons. And today on lorries we commonly see lifting axles (right).
naud-bobUsing the modern Bob trailer on a fat bike (left) is a similar and probably more efficient solution. The added effort in towing the loaded-down third wheel, rather than powering it as Naud’s 2WD bike could have done, is negated by the weight savings and the lower centre of gravity. You get the feeling Naud was merely experimenting with novel engineering solutions, as he discusses in the video below.

Naud’s three-wheel ride to Timbuktu (left) included at least 2000-km of piste. The route he took to the Mali border across the Tanezrouft is actually a firm gravel plain, about as easy surface to ride or drive as you get in the Sahara. Naud reckoned20kph was easy. Beyond that, it gets progressively rougher and sandier down towards the Niger River and, having ridden it on a moto in 1989, it’s hard to believe he managed to cycle the final section west along the Niger’s north bank to Timbuktu. It’s very sandy.
Even then, the Tanezrouft was the preferred route of the earliest Saharan motor crossings from the 1920s onwards by Citroen and Renaults (right; also using a ‘double-wheel’ idea to spread loads). The only problem in Naud’s time, was the Tanezrouft route lacked regular wells compared to the sandier but shorter Hoggar Route which Naud rode in 1980.

After visiting his childhood home in Blida, early in the trip while still unfit, it took Naud no less than eight hours to cover 14km on the climb to the 1300-m Col de Medea where the N1 tops out in the Atlas, before descending to the Saharan peneplain. Once fully loaded with 72 litres of water and another 60kg of gear, his 50-kilo monotrack three-wheeler weighed in at 180 kilos. That’s at least three times more than a modern touring bike, or five or six times heavier once fully loaded. Or, about the same as a small lightly loaded motorcycle ready for the desert. Imagine pedalling that!

Jean Naud died in 2011 aged 80. You can find his 1987 book – translated as Three Wheels to Timbuktu covering all his Saharan cycling adventures, on amazon France for €11.
His bike may still be on display at the Museum of Sport in Paris.

Garmin Topo North Africa Map Reviewed

garmintopThis review compares Garmin’s Topo North Africa Light map with easily downloaded and free OSMs, Garmin’s basic global base map and other digital maps, where available.

Navigating the Sahara
Having relied on them since before the advent of GPS, I’ve got to know my Sahara paper maps. well. Then when GPS came along, I could pinpoint my position with an accuracy that was more than adequate for desert travel. Some of these colonial-era maps such as the IGN 200s are cartographic works of art and unlike current nav technology, in the deep Sahara topography changes on a millennial scale. Tracks may become roads and villages become towns, but the desert itself remains relatively unchanged. Is there a benefit in having a tiny map on your GPS rather than simply a waypoint to aim for or a tracklog to follow, even if your position on the map is displayed live? That’s essential for navigating a busy city with a Nuvi. But the Sahara is more like the sea where more often what you want is…

… the big picture
garminmapA typical handheld device like my Garmin Montana (right) has a screen a little bigger than a playing card and which is hard to read on the move – especially on a bike. For me a ‘GPS’ (as opposed to a ‘satnav’ like a Nuvi – see below)) is best at displaying simple data like how far, how fast, how high or which way, not fine topographic detail. A paper TPC map can display six square degrees over some 18 square feet – what you call ‘the big picture’. That’s what you need travelling with a vehicle in an expansive area like a desert, while at close range concentrating on negotiating the terrain.
mushOn top of excellent paper mapping (now widely digitised), we also have the wonder of Google sat imagery (among others) providing a clarity that varies from stunning (being able to follow car tracks) to a brown mush (both shown right).
Google sat is great when planning, and now for a reasonable annual subscription, Garmin offer Birds Eye satellite imagery for the whole globe; the long-sought after ‘Google sat in your GPS’. With all these resources navigating in the Sahara couldn’t be easier.

Garmin Topo North Africa Light

garmin-coverageShort version:
Even though the free Olaf still measures up very well, the similar topographic detail of the Garmin means it’s well worth the £20, certainly over the plainer but also free OSMs.

Long version:
You download the Garmin Topo map directly into your device (takes about an hour) and only once your GPS is plugged into a computer, will it display on BaseCamp. Unplug the GPS and the map disappears from BaseCamp.
gar-atarSwitching BaseCamp between Olaf, OSMs and even the Garmin base map which comes free with a GPS unit, it soon becomes clear that the Garmin Topo has a level of detail and refinement that’s superior to the next best thing: Olaf. Occasionally at village level the OSM’s street-by-street detail is better, but that’s hardly vital. In towns and cities the extra shading distinguishes the gar-tantanGarmin from the plainer OSM, as shown for Tan Tan, right.
The chief difference is in the desert where the Garmin depicts relief and surface with more detail and clarity using shading, contours and colour where OSMs only use colour, and Olaf only uses contour lines which can be distracting. Look at the Atar region (RIM) above left – an area of escarpments, canyons and dunes – all are reasonably accurately shown on the Garmin Topo. There’s an anomaly on the Topo map on the left (bottom panel) in that the (presumably automatically recorded) elevation variation in dunes depicts them as lots of small hills (which in a way they are) – but only once they’re above a certain height. Identifying dunes with contours is not helpful, nor a cartographic convention. Shade is best
gar-msdThe piste and road detail on the Topo is pretty good: yellow for national highways, twin lines for secondary roads or piste, and a single line for a less used piste. A quick check in Morocco shows they’re all there; most of the ones I know are there in Mauritania too. In southern Algeria only a few main pistes are shown and certain ‘national highways’ are actually remote pistes never likely to be sealed. The Topo map would not be so useful here and in Libya is thinner still.
In any country dashed lines may well be walking tracks, but as far as I can see, there is no key or legend with the Topo map. Some POIs are there too – just fuel stations and post offices as shown on the Tan Tan map, above.
gar-pxIn places the Garmin copies the OSM’s annoying habit of again, marking high points (automatically?) as mountains which is a distraction, let alone inaccurate – for example when an escarpment gets shown as a string of peaks. If you drop the detail level enough notches on BaseCamp, these peaks (left) only disappear once all the useful tracks and place names have gone too. It’s great (and a bit puzzling) that this stuff is produced for free at all by OSM supporters, but the quickest flip to sat imagery would reveal the true nature of the relief.
So does the Topo map mean I’ll stop using Google Earth imagery in the planning, or paper maps on the piste. I don’t think so. In places like Morocco the extent of marked pistes can be (hopefully) converted into accurate tracklogs, but with better surrounding detail than OSMs. And, unlike Olaf, there’s no aggro importing into a modern, touch-screen GPS. When I want to quickly verify where I am, a glance at the Topo map may be adequate.

I’ve been using the Garmin Topo map quite heavily on Basecamp last couple of days, preparing a new edition of Morocco Overland. It’s an intuitive-reading map and I’ve found one benefit of using a Garmin map on Garmin software, is that when stringing out a track with the ‘create a route’ tool, it automatically snaps onto even the thinnest track on the map just like Google maps. But the Basecamp tool won’t do that with other installed maps like OSM or Olaf, or even the basic Garmin base map. Sometimes you have to trick the tool to go the way you want, but it makes stringing together hopefully accurate routes (as well as distances) very easy. Occasionally only Olaf will show a route you want to follow, in which case you make the route with lots of short, straight lines. No so hard.