In woodland glades and on heathlands, adders are sometimes seen basking in sunshine, before slithering away into the undergrowth to hide.
These secretive snakes can live for up to fifteen years, and are relatively small and stocky, with a length of 60-80cm and a weight of 50-100g. They are greyish in colour and have a dark and distinct zig-zag pattern down their backs. Like our fingerprints, they have markings on their heads, which can be used to tell individuals apart.