OS Explorer map 228 covers March & Ely in Cambridgeshire. This flat region is ideal for cycling & the long history of the area, including Roman remains, make it interesting to explore on foot. The annual ' March March march' is a walk from March to Cambridge that takes place in March, organised by Cambridge students. With this map you will receive a code for use on your i OS or Android smartphone or tablet. Find our more at Mobile Download FAQ. The OS Explorer map for March & Ely is available in both the standard paper version & weatherproof ' Active' version.