OS Explorer is the Ordnance Survey's most detailed map and is recommended for anyone enjoying outdoor activities such as walking, horse riding and off-road cycling. The series provides complete GB coverage and can now be used in all weathers thanks to OS Explorer - Active, a tough, versatile version of OS Explorer. Publisher: Ordnance Survey Author(s): Ordnance Survey Collection: OS Explorer Map Active Publication date: 2015 Dimensions: 231 x 138 x 18 Cover type: Sheet map, folded