The Paleolithic sites of India have been divided into primary, semi-primary and secondary categories, depending on their relationship with the place where the tools were first manufactured: original position, slightly removed from the original position through colluvial forces, and indeterminably removed from the original positions through alluvial agencies. The tools which occupy a vast space of the Indian literature on Paleolithic archaeology belong unhesitatingly to the last group.

The primary Paleolithic sites in India are rare because of the inadequate research. The cave sites are undoubtedly primary, but there are only three excavated cave sites: the upper Paleolithic Sanghao and Kurnool and the Acheulian rock-shelter III.F-23 at Bhimbetka. Sites buried in the alluvium or other deposits, such as those found in west Rajasthan, at Hunsgi in Karnataka, Paisra in Bihar. As far as the upper palaeolithic is concerned, there is more evidence from Baghor I in Sidhi, Madhya Pradesh, and the Kurnool caves of Andhra Pradesh.

There is a vast amount of literature on the Paleolithic tool types in India, which comfortably fit in the various categories of Paleolithic tools found in Africa, Europe and elsewhere in Asia. The modern classificatory system depends on a close analysis of different morphologi-cal attributes of the tool-type concerned, which is often statistically repre-sented. Another field of statistical enquiry in this field is the inter-site variability of different assemblages.

The fossils found in different parts of the Indian region evidence the existence of those species in the prehistoric era. A good source of the possible range of animals sharing the landscape with prehistoric humans is, of course, the extensive series of Pleistocene fossil animals found in different areas. The ancestral forms of modern cattle (Bos), horse (Equus) and elephant (Elephas) abound, and along with them occur forms of buffalo, varieties of deer, nilgai (Boselaphus tragocamelus), wild cats including lions, tigers and panthers. Interestingly, in the upper Pleistocene fossils from Susunia in Bankura, West Bengal, there is lion and in the fossils from the Kurnool caves of Andhra Pradesh there is rhino. Sheep or goat (Ovisl Capra) remains come from the upper Pleistocene contexts of the Kurnool caves and the upper Mahanadi valley. Ostrich roamed the grasslands of Maharashtra and Madhya Pradesh and, possibly, parts of Rajasthan. The richness of the Indian fauna was impressive even 50 years ago, and looked at from this perspective, one can only marvel at the possible range and density of animals sharing the prehistoric landscape with humans. It would be interesting to know more about the Pleistocene background of the present day living higher plants of the Indian region. The blue pine is supposed to have arrived early in the Pleistocene, and out of the immigrant Cedrus libanica from west Asia emerged during this period the most majestic of trees in the Himalayas.

In Sind, the distribution of such sites is conditioned by the locations of the outliers of the Kirthar range, Milestone 101 and the Sukkur-Rorhi hills being the two well-known centres of Paleolithic distribution here. Only surface occurrences have been noted but they cover the whole range of the Paleolithic from the lower to the upper. The Rorhi hills provide a good source of the raw material used for making Paleolithic implements, and on the basis of the study of the Acheulian workshop site of Ziarat Pir Shaban it has been inferred that it was used for the manufacture of hand axes which were later taken to the (contemporary) Acheulian basecamps. Since the earlier reports of lower Paleolithic artifacts from the Pahalgam sector, only upper palaeoliths have been reported from Kashmir. Considering that Ladakh has lower Paleolithic sites, there is no reason why they should not occur in Kashmir.

The Paleolithic evidence is more explicit and widespread in the Indian Siwalik belt from Jammu to Kangra and the lower areas of Himachal Pradesh and Punjab. There have been terrace-related studies of the relevant finds in the Beas-Banganga valley of Kangra and the Nalagarh-Chandigarh area of Punjab, but in view of the fact that such terrace-related studies have been discarded in the Soan valley, which provided the model of such studies in the Indian Siwaliks, no emphasis may now be put on the implementiferous `terraces` of the Beas-Banganga and other valleys. Perhaps a more useful approach will be to study the implementiferous occurrences of this region in terms of the basic Siwalik stratigraphy. The tremendous significance of the Siwalik sediments, `the thickest and most complete known Neogene sequence of fluvial deposits and palaeosols`, has recently been extensively commented upon.

There is an extensive spread of Paleolithic material in Rajasthan on either side of the Aravallis which also contain Paleolithic material as far north-east as Haryana and Delhi. Moreover, around Ajmer at the edge of the desert, the lower Paleolithic material occurs in sand sheet with angular slope wash debris, which was covered by another sand sheet deposit with calcification and root cast development between this and the earlier sand sheet deposit. The middle and upper Paleolithic material comes from buried soil which covers the later sand sheet deposit. The Hokra basin to the north-west of Ajmer showed rich middle Paleolithic working floors and upper Paleolithic working material. The middle Paleolithic was a flake industry with levallois cores or cores derived from the use of `prepared core technique`. In the upper Paleolithic industry here one finds burins, carinated scrapers, blades and blade cores of quartz and quartzite. In the Luni valley, also in the arid zone of Rajasthan, the middle Paleolithic tool-bearing sandy gravel directly overlies bedrock and is topped, successively, by silt and a sandy deposit. In this area lower palaeoliths also occur. Middle and upper palaeoliths are found near Jaisalmer as well, although the upper Paleolithic is not as abundant as the middle Paleolithic in this area.

In western Rajasthan, including the Thar Desert, prehistoric research has significantly advanced in recent years. In the Didwana area of the Nagaur district of west Rajasthan there are three major stratigraphic units, the first of which is a very extensive and continuous gravel ridge dating from late Tertiary-early Pleistocene and earlier than the human presence in the area. The two successive post-Jayal Formations, separated from the Jayal Formation by disconformities, are the Amarpura and Didwana Formations. The Amarpura Formation, as exposed in the Singhi Talav quarry near Didwana, is strongly mottled and well-laminated greyish silty calcareous clay, contain¬ing a rich early Acheulian material. The Amarpura Formation overlaps with the succeeding Didwana Formation which continues into the post-Pleistocene Holocene age.

A continuous cultural evolution has been traced from the early Acheulian to the middle palaeolithic in the Didwana area. In addition to these, in the 50 km stretch from Didwana to Jayal several Acheulian sites have been found, with the possibility of many more to be discovered. In contrast, there are fewer middle Paleolithic and later assemblages, suggesting an era of disorganized drainage and severe barrenness. Gujarat has been well researched from the point of view of prehistory, and here one can offer only a representative section of this research. In mainland Gujarat, the Sabarmati valley and its tributary valleys of Orsang and Karjan reveal a straightforward section of bedrock-gravel conglomerate-reddish silt-yellowish sandy silt or loess, with the lower palaeoliths occurring in the gravel conglomerate. Middle and upper Paleolithic tools have been reported from the eastern margins of the main¬land Gujarat plain.

The Narmada tract is the well-researched prehistoric area of Madhya Pradesh, though research has also been done in Damoh, Raisen, Upper Son valley and Mahanadi valley. In the Narmada valley, the stratigraphy offered by de Terra and Paterson showed three cycles of deposition on the bedrock and overlying laterite. At Samnapur in the central Narmada valley, a middle Paleolithic industry in what a semi-primary context of implementiferous rubble embedded in silt is found. In the Damoh area near Sagor in Madhya Pradesh, two gravels are found, the lower one with the lower Paleolithic and the upper one with the middle Paleolithic. Acheulian surface clusters in Raisen district were studied on the basis of their sizes and locations. In eastern Madhya Pradesh, a number of Paleolithic sites in the Mahanadi valley have been located by various scholars. The lower Paleolithic material comes only from surface occurrences, whereas the middle Paleolithic specimens are found associated with the river gravels. The upper Paleolithic industry of the area also seems to have been derived exclusively from the surface occurrences.

Apart from these sites, there are some other sites that are of equal importance. The rock-shelter-rich area of Bhimbetka near Bhopal in Madhya Pradesh has yielded evidence of a continuous prehistoric occupation from the late Acheulian onwards. In the Son valley section (Sidhi district) of Madhya Pradesh a clear assessment of the stratigraphic situation has been made. Palaeoliths occur all over Maharashtra, including the Konkan coast on the west and in the Wardha-Wainganga valleys in the east. The well-known stratigraphic profiles in archaeological literature are those of the Mula-Mutha Rivers in Pune, the Godavari in Nasik, the Pravara (a tributary of the Godavari) in Nevasa and the Tapti river system at Patne near Chalisgaon. The Dattawadi locality on the Mutha River in Pune shows the succession of gravel bed. The Hathi Well section at Nevasa on the Pravara shows loose gravel over the earlier gravel with lower Paleolithic tools. This second gravel contains a middle Paleolithic assemblage of scrapers, points and borers made on finer raw materials like jasper and chert.

Among the important Paleolithic sites, the name of Karnataka also figures in the list. In Karnataka, the Malaprabha-Ghataprabha system, a tributary system of the Krishna River, has been well known for its prehistoric sites since the nineteenth century. The lower Paleolithic-middle Paleolithic succession is represented by two succeeding gravels at various places such as Taminhal. In the Hunsgi-Baichbal valleys, the Acheulian artifacts are located either within the black soil of the surface or within brown clay which underlies the black soil. At Yedurwadi on the Krishna the artifact-horizon is gravel with a number of buried trees preserved as calcrete casts.

Climatically, the late Pleistocene picture in the Deccan seems to be that of semi-aridity till the end of the Pleistocene. Not much is yet known about the stratigraphy of quartz pebble tools from the Palghat district of Kerala, the only area with reported Paleolithic tools in the State. In Tamil Nadu, Paleolithic research is centred in the area near modern Chennai. Both coastal and inland Andhra are rich in Paleolithic sites. Various Andhra districts (Cuddapah, Kurnool, Chittoor, Nalagonda, Nellore, etc.) have been surveyed for Paleolithic remains, the sequence showing the usual two-fold gravel-silt succession. However, the Kurnool area of Andhra Pradesh possesses evidence of cave-sites occupied during the upper Paleolithic stage and the use of bone tools during this period, the only such categorical evidence available from the subcontinent.

Up along the east coast, Orissa is rich in Paleolithic remains too, some of her more prominent areas in this regard being the districts of Mayurbhanj, Dhenkanal, Sundargarh, Sambalpur, Phulbani, Bolangir, etc. In the Mayurbhanj area, the sequence above the bedrock shows the succes¬sion of mottled clay, lateritic conglomerate or what has been called a secondary laterite, and a sandy deposit or a thin layer of clay, whereas in many other areas the sequence shows a two-fold gravel-silt succession. All the three phases of the Paleolithic occur widely.

The western part of West Bengal, which is an upland region as opposed to the Gangetic delta, contains a large number of palaeolithic sites in the districts of Birbhum, Burdwan, Bankura, Purulia and Midnapur, primarily within the framework of the following section:

However, along the Tarafeni River in Midnapur, and possibly along a few rivers in Purulia, one finds the usual gravel-silt succession too, the lower palaeoliths being confined to the cemented gravel at the base of the sequence. The entire Chhotanagpur section of Bihar and a few areas beyond this plateau have yielded Paleolithic sites. The Chhotanagpur section comprises the former districts of Singhbhum, Ranchi, Palamau, Hazaribagh-Giridih and Santal Parganas whereas the non-plateau sections comprise the Nawadah plateau section of the Gaya district extending up to Rajgir and the Kharagpur forest area of Munger. The Paleolithic stratigraphy of Bihar varies widely, but in eastern Singhbhum it is basically an extension of the bedrock, mottled clay, lateritic conglomerate, sandy deposit section that has been observed in the western part of West Bengal and the Mayur-bhanj-Keonjhar section of Orissa. At a number of places in Singhbhum itself, the two-fold gravel-silt cycle occurs as it does in other areas of Bihar.

The Paleolithic remains of Uttar Pradesh are basically concentrated in the Lalitpur- Jhansi area, the Giri-Govardhan area near Mathura, the Singrauli area beyond Renukut and the Belan valley section near Allahabad. Only upper Paleolithic dates (C-14) are available from the Belan valley, the earliest point around 25,000 BP and the last one around 9,000 BC.

In the extreme north-west there is a series of dates (C-14) available for the Sanghao cave sequence which dates from the upper Paleolithic. At the sites of Jalalpur and Dina in the Potwar plateau the date of the lower Paleolithic has been dated 600,000-00,000 BP (palaeomagnetic stratigraphy) whereas a minimum date of 45,000 BP has been estimated for the upper Paleolithic at site 55 of Riwat in the same region. More positive reports from Assam and elsewhere in the north-east are found in India. An upper Paleolithic industry in fossil wood has been found in the Haora and Khowai river valleys near Agartala in the western part of Tripura. Implements like hand axes, hand adzes, blades, burins, backed knives, points, etc. made of a type of fossil-wood which possesses a flinty core beneath the fibrous woody surface were found below the present surface.

The Paleolithic sites are, thus, scattered all over India and the excavated articles found from these places contribute to the study of archaeology of India.