On a cold and frosty day, it is perfect weather for a winter walk. Often the air is still, the sky bright and the colours of the earth simply glow. Take a magnifying glass or fresnel lens and just enjoy looking at the frosty "jewels" decorating the plants.

For older children, working out how this hoarfrost was created is an interesting challenge. Essentially it's frozen water that's taken on a crystal form. Water vapour in the atmosphere has frozen onto the colder plant surface.

Altogether quite remarkable.