Question: Petroglyphs on Ingaro isalnd indicate it has been innhabited since an era that lasted until what year?

<P0-S0> Ingarö is an island in Värmdö Municipality, Stockholm County. <P0-S1>  The chief settlement is called Brunn. <P0-S2>  With an area of 63 km, it is the 16th biggest island in Sweden. <P0-S3>  Petroglyphs indicate that the island has been inhabited since the Nordic Bronze Age. <P0-S4>  For most of the 20th century the resident population decreased, while at the same time many vacation homes were built. <P0-S5>  However, in recent years population has grown as new homes are being built and vacation homes are being converted into permanent homes. <P0-S6>  Improved communications has made it feasible to commute to Stockholm. <SEP> <P1-S0> The Nordic Bronze Age (also Northern Bronze Age, or Scandinavian Bronze Age) is a period of Scandinavian prehistory from c. 1700–500 BC. <P1-S1>  The Bronze Age culture of this era succeeded the Nordic Stone Age culture (Late Neolithic) and was followed by the Pre-Roman Iron Age. <P1-S2>  The archaeological legacy of the Nordic Bronze Age culture is rich, but the ethnic and linguistic affinities of it are unknown, in the absence of written sources. <P1-S3>  Some scholars also include sites in what is now Estonia, northern Germany and Pomerania, as part of its cultural sphere. <SEP> <P2-S0> AD 1 (I), 1 AD or 1 CE is the epoch year for the Anno Domini calendar era. <P2-S1>  It was a common year starting on Saturday or Sunday, a common year starting on Saturday by the proleptic Julian calendar, and a common year starting on Monday by the proleptic Gregorian calendar. <P2-S2>  In its time, year 1 was known as the Year of the Consulship of Caesar and Paullus, named after Roman consuls Gaius Caesar and Lucius Aemilius Paullus, and less frequently, as year 754 AUC ("ab urbe condita") within the Roman Empire. <P2-S3>  The denomination "AD 1" for this year has been in consistent use since the mid-medieval period when the anno Domini (AD) calendar era became the prevalent method in Europe for naming years. <P2-S4>  It was the beginning of the Christian/Common era. <P2-S5>  The preceding year is 1 BC; there is no year 0 in this numbering scheme. <P2-S6>  The "Anno Domini" dating system was devised in AD 525 by Dionysius Exiguus. <SEP> <P3-S0> The Piney Creek West Site is a prehistoric rock art site located north of Piney Creek in Piney Creek Ravine State Natural Area in Randolph County, Illinois. <P3-S1>  The site consists of four petroglyphs painted on the inside of a rock shelter and a pictograph painted on the outside. <P3-S2>  The interior petroglyphs include an abstract shape, two curved lines, and a serpentine line with a pit at one end; two of the petroglyphs are filled in with ochre pigment, representing the only intact example of this painting technique in Illinois. <P3-S3>  The pictograph, which has deteriorated badly, depicts a human left hand; nearby flecks of paint from an unrecognizably faded figure likely indicate the site of the right hand. <P3-S4>  The paintings were likely added during the Late Woodland period, which lasted from 450 to 900 A.D. <P3-S5>  The serpentine figure inside the shelter suggests that the site had spiritual significance, as it resembles other prehistoric rock art depicting shamanic trance states.