Wellington boot bags/welly bags are an essential, when your welly wanders get your boots covered in mud and dirt. These boot bags easily carry adult wellies and also work for multiple pairs of kids' wellies. Some Mums use them to carry school shoes when their kids walk to school in their warm wellies.
Our welly bags have a tough nylon exterior, with a ventilation panel at the back and an easy-open double zip at the front and a sturdy carrying handle. There's an inside pocket which is useful for cloths or stashing things out of sight. It will fold flat when empty so doesn't take up any room.