The use of fire and bonfires, light and heat in the darkness of night, stems from the customs of pre-Christian ancestors, as so many of our customs do. In many parts of Europe, this midsummer feast was celebrated with singing, dancing and of course, festive food. Food that can be cooked over a bonfire, or barbeque is especially appropriate for this feast. For many families, a bonfire may be a somewhat impractical proposition. Not many landlords take kindly to conflagrations on apartment balconies, and many municipalities ban outdoor fires altogether for some very good reasons.
Candle lanterns are a safe, property-respecting, fun alternative.
They're really pretty too. Any size of can is suitable, as long as your hand and a candle will fit inside it. Wash the can well, and make sure the lid hasn't left any sharp bits along the top edge. Bend them down securely or cut them off if necessary. Using a marker, or crayon, mark out a design on the outside of the can.