Celtic archeological evidence can be found in Western Europe and countries bordering the north shore of the Mediterranean Sea. Collections of Celtic remains could be housed in museums around the world. Traces of Celtic civilization can be seen in modern place names.
Locations in this category must be of physical remains/ruins of preliterate (prior to the Christian era) Celtic civilization or "in-situ" reconstructions, or collections/pieces of archeological significance, for example in museums. Additionally, locations can be of city/village/dorf/named place limit signs or major landmarks of cities whose name can be traced to Celtic origin (Only 1 waymark per city/village/dorf/named place please). Examples : Paris and Chartres. (No New World cities named after the Old World original please).
Locations associated with the modern history of the ancestors of the Celts (Irish, Scots, Welsh, etc.) are excluded.
See following for more information on this civilization.
This monolithic culture spread from Ireland to Asia Minor (the Galatians of the New Testament). The Celts even sacked Rome in 390 BC and successfully invaded and sacked several Greek cities in 280 BC. Even though there is no written record of the Celts stemming from their own documents, a fair picture of them can be pieced together from archeological evidence as well as historical accounts from other cultures.
The period of Celtic dominance in Europe began to unravel in the first centuries AD, with the expansion of Rome, the migrations of the Germans, and later the influx of an Asian immigrant population, the Huns. By the time Rome fell to Gothic invaders, the Celts had been pushed west and north, to England, Wales and Ireland and later to Scotland and the northern coast of France.
Most of what is known about Celtic life comes from Ireland. Early Celtic societies were organized around warfare. Although classical Greek and Roman writers considered the Celts to be violently insane, warfare was not an organized process of territorial conquest. Among the Celts, warfare seems to have mainly been a sport, focussing on raids and hunting. In Ireland, the institution of the fianna involved young, aristocratic warriors who left the tribal area for a time to conduct raids and to hunt.
Celtic society was based almost entirely on pastoralism and the raising of cattle or sheep; there was some agriculture in the Celtic world, but not much. The importance of cattle and the pastoral life created a unique institution in Celtic, particularly Irish, life: the cattle-raid. The stealing of another group's cattle was often the proving point of a group of young warriors.
There was no urbanization of any kind among the Celts until the advent of Roman rule; in Ireland, urbanization did not occur until the Danish and Norwegian invasions. Society was not based on trade or commerce; what trade took place was largely in the form of barter. Celtic economy was probably based on the economic principle of most tribal economies: reciprocity. In a reciprocal economy, goods and other services are not exchanged for other goods, but they are given by individuals to individuals based on mutual kinship relationships and obligations.
It is almost certain that the material world of the Celts was suffused with divinity that was both advantageous and harmful. Certain areas were considered more charged with divinity than others, especially pools, lakes and small groves, which were the sites of the cental ritual activities of Celtic life. The Celts were non-urbanized and according to Roman sources, Celtic ritual involved no temples or building structures—Celtic ritual life, then, was centered mainly on the natural environment. Celtic ritual life centered on a special class, called the druides or "druids" by the Romans, presumably from a Gaulish word. Although much has been written about druids and Celtic ritual practice, next to nothing is known about either. As a special group, the druids performed many of the functions that would be considered "priestly" functions, including ritual and sacrifice, but they also included functions that would be placed under "education" and "law." These rituals and practices were probably kept secret—a tradition common among early Indo-European peoples—which helps to explain why the classical world knows nothing about them. The only thing that the classical sources attest is that the druids performed "barbaric" or "horrid" rituals at lakes and groves; there was a fair amount of consensus among the Greeks and Romans that these rituals involved human sacrifice. This may or may not be true; there is some evidence of human sacrifice among the Celts, but it does not seem to have been a prevalent practice.
The earliest Celts who were major players in the classical world were the Gauls, who controlled an area extending from France to Switzerland. It was the Gauls who sacked Rome and later invaded Greece; it was also the Gauls that migrated to Asia Minor to found their own, independent culture there, that of the Galatians. Through invasion and migration, they spread into Spain and later crossed the Alps into Italy and permanently settled the area south of the Alps which the Romans then named, Cisalpine Gaul.
Two Celtic tribes, the Cimbri and the Teutones ("Teuton," an ethnic for Germans, is derived from the Celtic root for "people"), emigrated east and settled in territory in Germany.
The Gaulish tribes or territories frequently built fortifications that served as the military and political center of the region. These fortified centers took their names from the larger tribe—for instance, Paris took its name from the tribe of Parisi and Chartres was originally named after the tribe, the Carnuti, which had built it.
In Britain the Romans found a disunified group of tribal kingdoms organized around the same logic of warfare as the Gauls. Most of the tribes were new arrivals—the bulk of southern Britain had been conquered by the Belgae from northern Gaul. The Celts in the north and in Wales fiercely resisted Roman culture, and the Romans never even set foot in Ireland. On the whole, the Romans more greatly respected and tolerated Celtic institutions and religions in Britain, so there was considerably less assimilation than in Gaul. Britain fell prey to the same Germanic emigrations and invasions that spread across Gaul, Spain, and Italy. The Saxon emigration began in eastern England until they spread entirely across lowland England. The mountainous areas to the west (Wales) and the north (Scotland), however, remained Celtic, as did Ireland. By the end of the fifth century AD, only Wales, Scotland, and Ireland remained of the great Celtic tribal kingdoms that had dominated the face of Europe.
It was in Ireland that Celtic culture and institutions lasted the longest—although Christianity was introduced at an early date, Ireland did not suffer any major invasions or cultural changes until the invasions of the Norwegians and the Danish in the eighth century. The Irish also represent the last great migration of Celtic peoples. In the fourth and fifth centuries, the Irish crossed over into Scotland and systematically invaded that territory until they politically dominated the Picts who lived there. The settling of Scotland in the fifth century was the very last wave of Celtic migration.
For a good overview of the Celts you can go to The Celts