The A-337 links La Calahorra, below its castle on the northern side of Sierra Nevada, with Laroles in the Alpujarra, crossing the range over the Puerto de la Ragua. It is a short ride but a complete one: you climb from the Guadix high plain, crest the pass and drop down the southern face towards the Alpujarra villages. It works as a ride on its own or as a natural link between the Guadix area and a loop through the Alpujarra.
The contrast between the two sides is the main draw. To the north you leave the open, dry landscape of the Marquesado; at the top the terrain is high mountain, and to the south the valley closes in and terraced fields and the white villages of the Alpujarra appear. The road runs through the municipalities of La Calahorra, Ferreira and Nevada, and enters the Parque Nacional de Sierra Nevada and the Geoparque de Granada.
It is about 30 km and takes around 50 minutes without stops. Altitude ranges from just over 1,000 m to about 2,050 m at the top, so the weather can change quickly: it may be cold and windy up high even when it is warm below. Pack a warm layer, bear in mind that mountain roads can have loose livestock or gravel on the surface, and check conditions on the pass before setting off in the colder months.