The essential map for outdoor activities in Harlech, Porthmadog & Bala. The OS Explorer Map is the Ordnance Survey\'s most detailed folding map and is recommended for anyone enjoying outdoor activities including walking, horse riding and off-road cycling. This map now comes with a digital version which you can download to your smartphone or tablet.FeaturesDolgellauPorthmadogY BalaSnowdonia National ParkGwyneddClwyd1:25 000 scale (4 cm to 1 km \' 2.5 inches to 1 mile)This map comes with a digital version which you can download to your smartphone or tablet.