The approach to Leyva was a little unclear in the 2013 guidebook. Thanks to Chris Heald who has sent a clarification and here is a new map as well.
Follow the motorway south from Alicante, round Murcia (80km) then continue southwards for another 22km to a turn off that runs into the town of Alhama de Murcia. Turn right in the centre of town onto the C3315 (signs for Mula) and follow this to a left turn about 6km after leaving the town, signed ‘El Berro 7.5km’. (Straight on is also signed to ‘El Berro’ but is 10km). Drive steeply uphill to a turning on the right to El Berro but continue straight for 3 kms. Turn right onto a tarmac road with white Regional Park signs. After 200m go right again onto good dirt road (Regional Park signs). Continue to the parking area after 1km. Take main track past green gates. The cliffs are a 30-50 minute walk up the main track.