Forty kilometres from Logroño, Calahorra is the main town of La Rioja Baja, the southeastern part of the province. After the wine towns of the Rioja Alta it’s a disappointment, and there’s no pressing need to stop, though its parador brings some out this way. However, Calahorra does offer an attractive back-country route to Soria, via Arnedo, 12km southwest of town, where the scenery suddenly changes from cultivated flatland to vivid red rock, punctured by hundreds of caves, both natural and man-made, used in the past as houses and hermitages. From here – past attractive riverside Arnedillo, until reaching the tiny valley-bottom village of Yanguas, 30km southwest – the LR115 makes a twisting journey through the narrow Río Cidacos gorge, before climbing up over the bare tops for the sweeping run into Soria, another 50km to the south. It takes a couple of hours all told from Calahorra to Soria, though it’s much the best idea to break in the middle at Enciso for a spot of dinosaur-hunting. A hundred and twenty million years ago (in the early Cretaceous period), the southeastern part of La Rioja was a steamy marshland where dinosaurs roamed, leaving their footprints in mud that later fossilized, and you can spend an enjoyable day in the area tracking the tracks.