The RN4 road from Majunga to the Parc National d’Ankarafantsika twists and turns to begin with as it crosses the dry hills around Berivotra. American palaeontologists have leased a great escarpment on the south side of the road where a tributary of the Betsiboka has carved into the rock, exposing a rich array of dinosaur fossils – many of them new species. Some 44km southeast of Majunga, if you’re independently mobile you can stop at the side of the road and you’ll quickly find the evidence – fascinating and sizeable lumps of fossilized limb bones, some showing the hollow structure of the dinosaur’s bird-like ancestry. The impressive carnivore Majungasaurus was found here. On the north side of the road, 6km further east, a set of signboards explains the area’s importance for dinosaur research – and the importance of not disturbing the fossils.
East of Berivotra, as you come down onto the plain, the road straightens out and, following the broad Betsiboka valley upstream, you pass the turning to Marovoay (reputed to be the hottest town in Madagascar; market day Friday), before entering the Ankarafantsika forest. Some 40km southeast of Ankarafantsika, the RN4 meets the RN6 from Diego Suarez at the market town of Ambondromamy (main market on Tuesday).
Less than 90km further south, Maevatanana – a large town on the upper Betsiboka, with a BOA bank with an ATM – is a common meal stop. After Mahatsinjo, 110km further south, the RN4 starts to climb in earnest, switchbacking up onto a high ridge. The temperature and scenery change very quickly and you’re soon in a landscape of grassy hills dotted with conifers and interspersed with farm plots and rice paddies – the typical highland landscape.