KARACHI, Jan 2: Hectic efforts are under way to gather complete information regarding three archeological sites in the country, so that these could be considered by Unesco for the status of the World Heritage Sites, it is learnt.

According to sources, the government had submitted the names of Mehrgarh, Rehman Dheri and Harappa to the Unesco, so that these could be considered an extension of the Moenjodaro World Heritage Site, and a part of the Indus Valley Civilization, but as the information provided earlier regarding these sites was incomplete, Unesco had returned the proposal requesting for complete information.

The sources said that Unesco's World Heritage Centre, in its communication to the government, had mentioned that the World Heritage Committee had decided that only the full and complete nominations would be examined.

The missing information could be submitted by Feb 1, 2005, so that it could be examined, says the Unesco communication. Mehrgarh is located in Kachi plains close to the mouth of the Bolan Pass, next to the west bank of the Bolan River near Dhadhar village some 30 kilometres from Sibi in Balochistan.

The archeological sequence of the Mehrgarh is around 11-metre deep and spanning a period between the seventh and third millennium BC - from 6500 BC to 2500 BC. Covering an area of over 250 hectares, most of the ruins at Mehrgarh are buried under alluvium deposits, though some structures could be seen eroding on the surface. Currently, the excavated remains at the site comprise a complex of large compartmental mud-brick structures.

Built of hand-formed plano-convex mud bricks, the function of these subdivided units is still not clear, but it is thought that many were used for storage rather than residential purposes. A couple of mounds also contain formal cemeteries, parts of which have been excavated.

Although Mehrgarh was abandoned by the time of the emergence of the literate urbanised phase of the Indus civilization, its development illustrates the development of the civilizations's subsistence patterns as well as its craft and trade.

The Rehman Dheri site, situated some 22 kilometres north of Dera Ismail Khan, west of Indus river, and 1.5 kilometres to the west of main Bannu-D I Khan highway, is in the NWFP. The archeological sequence of Rehman Dheri is over 4.5 metres deep and covers a sequence of over 1,400 years - beginning at 3,300 BC and up to 1,900 BC.

The 40-hectare site comprises a rectangular-shaped mound covering some 22 hectares that stands over 4.5 metres above the surrounding fields. The final 'occupational phase' of the site is clearly visible on the surface of the mound and also through air photographs.

It consists of a large walled rectangular area with a grid-iron network of streets and lanes dividing the settlement into regular blocks. Walls delineating individual buildings and street frontages are clearly visible in early morning dew or after rain and it is also possible to identify the location of a number of small-scale industrial areas within the site market, as they are, by eroding kilns and scatters of slag.

The surface of the mound is littered with thousands of shreds and artifacts, slowly eroding. Rehman Dheri probably represents Asia's oldest and the best preserved settlements, which is exceptionally significant in understanding the emergence of urbanization in the region under the Indus Valley Civilization.

Harappa is situated some 26 kilometre southwest of Sahiwal (former Montgomery) in southern Punjab. The ruins consist of a series of low archeological mounds and cemeteries to the south of a dry bed of Ravi river.

The archeological sequence at Harappa is over 13-metre deep and spans the period between fourth and second millennium - 3300 BC and 1300 BC. Being located near the old course of Ravi river, its inhabitants had an easy access to trade networks, aquatic food-stuffs, as well as to the water for drinking and cultivation, which perhaps was the reason why the site remained occupied for so long.

Although covering 150 hectares, the Harappa complex, alongwith its buffer zone, comprises eight mounds and two cemeteries - the remaining being buried deep beneath the surrounding agricultural land and the modern village of Harappa.

The site's sequence stretches from the fourth to the second millennium BC, and whilst there are a limited number of open sections, the only exposed structures date to third millennium.

A Gupta period temple, a partially conserved mosque, and the recently excavated foundations of a Mughal Serai, besides the ruins of a colonial police station are also located nearby.

The Harappa site was first affected severely when thousands of bricks were removed from the vicinity for railway ballast in 1850s, which destroyed marks of many of the late phases of its occupation.

Expansion of canal-irrigated agricultural fields resulted finally in archeological excavations, which completely destroyed many structures excavated subsequently in the 1940s.

Other sites in the country that have been declared as the World heritage Sites by Unesco are Archeological Ruins of Moenjodaro, Makli Hill monuments, Lahore Fort, Shalamar Gardens, Takh Bhai (Mardan, NWFP), Taxila Valley and Rohtas Fort (Jehlum).