What was the Paleolithic period like in Aomori Prefecture!? How is it related to the Jomon period? - Archaeological Sites in Aomori Prefecture: Paleolithic Sites ①

Aomori Prefecture suffered extensive damage from heavy snowfall in the winter of 2026. The average winter temperature is around 2°C even during the day, making it extremely cold

It is estimated that during the Jomon period, 6,000 years ago, the average temperature even in the harshest winters was around 2°C, with daytime temperatures of 5-6°C. This corresponds to the current average temperatures of Sendai City in Miyagi Prefecture and Niigata City in Niigata Prefecture. The Jomon period was a time when temperatures rose after the end of the last ice age, and 5-6°C in winter was the highest temperature during the Jomon period, indicating that Aomori Prefecture was much more livable than it is today. In July, the average temperature was 24-26°C, which was about 3°C ​​higher than it is now

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Eight archaeological sites in Aomori Prefecture are registered as UNESCO World Cultural Heritage sites

Archaeological sites in northern Japan, primarily from the Jomon period, have attracted worldwide attention. Eight sites in Aomori Prefecture, along with six sites in Hokkaido, one in Iwate Prefecture, and two in Akita Prefecture, were registered as a UNESCO World Cultural Heritage site, "Jomon Archaeological Sites in Hokkaido and Northern Tohoku."

Part of the Jomon Archaeological Sites in Hokkaido and Northern Tohoku

• Hokkaido
  • Kakinoshima Site, Kitakogane Shell Mound, Ofune Site, Irie Shell Mound, Takasago Shell Mound, Kiusu Circular Embankment Burial Mounds, Washinoki Site (Associated Jomon Archaeological Sites in Hokkaido and Northern Tohoku)
• Aomori Prefecture
  • The Odaiyamamoto Site, Tagoyano Shell Mound, Sannaimaruyama Site, Futatsumori Shell Mound, Omakino Site, Omorikatsuyama Site, Kamegaoka Stone Age Site, Korekawa Stone Age Site, and Choshichiyachi Shell Mound (Associated with the Jomon Archaeological Sites of Hokkaido and Northern Tohoku)　　
• Iwate Prefecture
  • Goshono Ruins
• Akita Prefecture
  • Ise-do-tai Ruins, Oyu Stone Circle

In addition to its World Heritage sites, Aomori Prefecture has numerous archaeological sites dating from the Paleolithic period to the Heian period. There are 4,893 such sites in total, of which 3,581 are Jomon period sites (as of April 2023, according to the Aomori Prefectural Board of Education)

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The definition of an archaeological site is a trace of human activity

Before moving on to Jomon period archaeological sites, I'd like to organize the information on earlier sites based on the latest data and theories

*This article is based on research results and dates up to February 2026. However, please note that archaeological survey results and artifact dating are updated daily, so the information in this article may differ from the latest research findings

*Main references for this article

This includes the Aomori Prefectural History, the Aomori Prefectural Museum of Local History, the National Museum of Japanese History, and the Gunma Prefectural Museum of Natural History. It also includes interviews with archaeological site management facilities, related local government documents and facilities (in the case of Aomori Prefecture), National Geographic (in the case of overseas locations), the Department of Ethnology and Archaeology, Faculty of Letters, Keio University (investigation of the Shiri-Ro-Abe Cave), the Graduate University for Advanced Studies, the Ministry of Land, Infrastructure, Transport and Tourism, and press releases

First, let's clarify the definition of a site (or archaeological site). A site is a place where tools used by human ancestors have been found. While there are various types of tools, the earliest tools used were stone tools, and therefore sites are generally considered to date from the Paleolithic period onward. Even if fossils of animals or fish are found, if no tools used by humans are found, it is not considered a site. In such cases, it is often simply called a fossil locality (or just a locality)

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The world's oldest archaeological site is the Lomekwi site in Kenya, dating back approximately 330 years

From the perspective of ape history, the oldest archaeological site in the world is the Lomekwi 3 site on the western shore of Lake Turkana in northwestern Kenya, Africa. Stone tools unearthed there in 2011 were dated to approximately 3.3 million years ago. This revealed the astonishing fact that early hominids who made stone tools existed 3 million years before the appearance of humans (Homo sapiens) (approximately 300,000 years ago). This 3.3 million year ago is considered the beginning of the Paleolithic period

As for human remains, stone tools and skull fragments unearthed from the Jebel Irhoud site in Morocco (Africa) were announced in 2017 to be approximately 310,000 years old, making it the world's oldest known human habitation site

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During the Ice Age in Aomori Prefecture, was it possible to walk across the Tsugaru Strait?

The Paleolithic period in the Northern Hemisphere lasted from approximately 3.3 million years ago to about 11,700 years ago. During that time, the Earth was in an ice age, experiencing alternating periods of warming and cooling. Ice ages have occurred intermittently from about 2.9 billion years ago to the present, and it is believed that the last ice age (the Last Glacial Period) began around 110,000 years ago and is still ongoing (we are currently in an interglacial period (a warm period) that began around 117,000 years ago)

The coldest period of the last ice age was the Last Glacial Maximum (LGM), which began about 70,000 years ago and peaked around 20,000 years ago. High-latitude regions such as central and northern Europe and North America were covered in ice, and sea levels were about 120 meters lower than they are today because the water had turned to ice. In northern Honshu, such as Aomori Prefecture, temperatures were about 10°C lower than they are now, the distance to the continent was shorter, and the sea was shallower. It is also thought that the Sea of ​​Japan was covered in ice

The Tsugaru Strait, which is currently about 140 meters deep, is estimated to have been only about 20 meters deep at its deepest point, connecting Aomori Prefecture and Hokkaido. It is also thought that there may have been times when the strait was frozen over, and that parts of it were connected by ice bridges. Mutsu Bay is still shallow today, with a maximum depth of about 60 meters, and was land during the Ice Age. However, it is said that the plains south of Honshu, including Aomori Prefecture, were never covered in ice due to the influence of the Kuroshio Current (a warm current)

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The Paleolithic and Neolithic periods are globally standardized names. The Jomon and Yayoi periods, on the other hand, are unique to Japan

Around 11,700 years ago, the Earth began to warm up rapidly. This period is globally defined as the end of the Paleolithic era. During the Paleolithic period, people used rocks as sharp objects by striking or smashing them, but humans used their ingenuity to devise a method of polishing stones by hand. This marked the beginning of the next era (the Neolithic era)

The Paleolithic and Neolithic periods were defined by the British archaeologist John Lubbock (1834-1913) in 1865

The Paleolithic period is a compound word from the Greek words Paleos (old) and lithos (stone), meaning "the era in which chipped stone tools were used." It spans from 3.3 million years ago to 11,700 years ago, coinciding with the final glacial period. No pottery has been found at archaeological sites in Europe or North America during this time

In Japan, the term "Paleolithic period" also refers to this time period. However, in 1999, pottery discovered at the Odaiyamamoto site in Aomori Prefecture (Sotogahama Town, World Cultural Heritage site, nationally designated important cultural property, and nationally designated historic site) was found to have been made approximately 16,500 years ago. This revealed that the Jomon period began 5,000 years earlier than the end of the Paleolithic period (approximately 17,000 years ago)

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Jomon period and Paleolithic period sites are classified based on whether or not pottery has been discovered

However, not all Paleolithic sites excavated in Japan have yielded pottery. Pottery is found not only at sites predating the "Ohirayama-moto Site," but also in many sites after it. Therefore, for classification purposes, Paleolithic and Jomon period sites are used separately

■ Jomon period sites: Beginning around 16,500 years ago during the Paleolithic period [sites where pottery has been unearthed]

■Paleolithic Sites: Sites dating up to around 11,700 years ago, when the Paleolithic period ended, where only stone tools showing traces of the Paleolithic era have been unearthed

For example, at the Ohirayamamoto site, pottery was unearthed from the first excavation site. Excavation work was then carried out in the surrounding areas, but so far no pottery has been found. For this reason, the first site was named [Ohirayamamoto Site I] and classified as a Jomon period (initial stage) site, while the [Ohirayamamoto Site II] and [Ohirayamamoto Site III], which were excavated later, are classified as Paleolithic sites for convenience. If pottery is found at any site other than Site I, those sites will also be classified as Jomon period (initial stage)

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Archaeological sites with "Stone Age" in their name are actually Jomon period sites

There's another source of confusion within Japan. In Aomori Prefecture, among the World Heritage sites, there are sites with the word "Stone Age" in their names, such as the "Kamegaoka Stone Age Site" and the "Korekawa Stone Age Site." What period exactly is this Stone Age?

This is a uniquely Japanese expression that was used before the term "Jomon period" became widespread

The term "Jomon period" only became widely used after World War II, replacing "Stone Age," and only after it began to be used in textbooks. The "Kamegaoka Stone Age Site" (discovered during the Edo period) and the "Korekawa Stone Age Site" (discovered during the Taisho period) are actually Jomon period sites, but the names given to them before the term "Jomon period" existed are still used as their official names, which has led to confusion

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In early 2026, a surprising announcement was made: "There were lions in Japan." There are also lions in Aomori Prefecture

A historic paper stating that "it was not tigers but lions that inhabited Japan" was published on January 26, 2026 (New York time) in the prestigious American scientific journal, the Proceedings of the National Academy of Sciences. The paper was published by an international joint team from Japan's Graduate University for Advanced Studies and countries such as China and Denmark, and was covered by many media outlets in Japan. Moreover, of the 26 samples collected from all over Japan that had previously been thought to be tigers, one of the five fossils that were ultimately selected to determine that the animal was a lion was unearthed from Shiriyazaki on the Shimokita Peninsula in Aomori Prefecture. It has now become clear that lions also inhabited Aomori

Despite the discovery of 3,581 Jomon period sites in Aomori Prefecture, there are only a little over 30 Paleolithic sites. Compared to the more than 10,000 Paleolithic sites excavated throughout Japan, Aomori Prefecture has an extremely small number. Even among these few sites, there are some that have attracted worldwide attention, such as the "Ohirayamamoto Site." In "Aomori Prefecture's Archaeological Sites: Paleolithic Sites ②," we will explore why there are so few Paleolithic sites in Aomori Prefecture and provide an overview of the Paleolithic sites in Aomori Prefecture

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