A sand castle is a type of sand sculpture resembling a miniature building, often a castle. The two basic building ingredients, sand and water, available in abundance on a sandy beach, so most sand play takes place there, or in a sandpit. Tidal beaches generally have sand that limits height and structure because of the shape of the sand grains. Good sand sculpture sand is somewhat dirty, having silt and clay that helps lock the irregular shaped sand grains together.
A variant on the sandcastle is the drip castle, made by mixing the sand with water and dripping it from a fist held above. Some refer to the technique as “dribbling.” When the slurry of sand and water lands on existing sand structures.
Sand castles are typically made by children, simply for the fun of it, but there are also sand sculpture contests for adults that involve large, complex constructions.
Construction of the sand sculptures
Sand grains will not stick together unless the sand is reasonably fine. While dry sand is loose, wet sand is adherent if the proper amounts of sand and water are used in the mixture. According to the BBC TV programme Coast, the ideal ratio is eight parts dry sand to one part water. When the sand dries out or gets wet, the shape of a structure may change; “landslides” are common. Furthermore, the mixture of fine (mostly sharper) and coarse sand granules is very important to achieve good “sand construction” results. Fine granules can be rounded by the natural influences of seas, rivers or fluvials, in turn negatively influencing the bonding between the individual granules. Research is thus necessary to find the most suitable sand to achieve an optimal, landslide-free construction.
Shovels are the main construction tool, although some people use only their hands. Water from the sea can brought to the building site with a bucket or other container. Sometimes other materials, such as pieces of wood, are added to reinforce structures.
Sand sculpting as an art form has become very popular in recent years. Hundreds of annual competitions are held all over the world. Techniques can be quite sophisticated, and record-breaking achievements have been noted in the Guinness World Records. Sometimes contests are staged as advertising or promotional events.
Some sandcastle artists are purists, using no artificial materials, formwork, coloring, adhesive or heavy machinery. One such purist is G. Augustine Lynas, who has been building public sand sculptures for over 50 years. However, in sand sculpting competitions, the rules often require that the finished sculpture be sprayed with a stabilizing coating that preserves it and allows the work to be properly judged and enjoyed by spectators. Coated sculptures can last for months.