An archaeologist is a person who excavates objects of interest from underground and sometimes from underwater. The place where the archaeologist works is called a site. Sometimes sites are found by accident, such as during the construction of new motorways. In 2007, an important discovery was made close to the Hill of Tara, where the new M3 motorway is being built. Sites can also be found by examining aerial photographs or from listening to old legends. Upon arrival at the site, the archaeologist must plan the excavation very carefully. A survey of the site is made and all the topsoil is removed. The area is then divided into grids and a site map is produced.
When the archaeologist begins his or her work, tools such as brushes, shovels, trowels and sieves are used. The archaeologist has to work very carefully and has to be very patient. Objects that are found are called artefacts and these might include bones, pottery, weapons or jewellery. Everything is photographed and each artefact is carefully labelled and then sent to a laboratory. The exact age of artefacts can be determined by a scientific method called carbon 14 dating. Wooden artefacts can be dated using dendro-chronology. When archaeologists find human bones, these can also be analysed to determine age, cause of death and the health of that person when he or she was living. Many artefacts finally end up in museums where members of the public can go to view them.