To quote from John Grepsteads's Pinhole site:

Pinhole photography is lensless photography. A tiny hole replaces the lens. Light passes through the hole; an image is formed in the camera. Pinhole cameras are small or large, improvised or designed with great care. Cameras have been made of sea shells; many have been made of oatmeal boxes, coke cans or cookie containers; at least one has been made of a discarded refrigerator. Cameras have been cast in plaster like a face mask, constructed from beautiful hardwoods, built of metal with bellows and a range of multiple pinholes. Station wagons have been used as pinhole cameras – and rooms in large buildings. Basically a pinhole camera is a box, with a tiny hole at one end and film or photographic paper at the other

Right: A small inlet in Southern Brittany