Radiocarbon tests, conducted by a Swiss archeologist and an anthropologist, have dated the archeological finds at Jakar, Bumthang, to two periods: end of the eighth to the beginning of the ninth century and the mid-16th century.  
    Archeologist Reto Blumer and his anthropologist wife Frederique Vial returned to Bhutan earlier this year, with a geologist and a biologist from the Swiss-Liechtenstein Foundation for Archeological Research Abroad, to continue their research. 
    Last year they identified the four structures first found while excavations were being carried out for the construction of a new RNR-Research Centre in Jakar two years ago and have made more discoveries recently. 
    The first, an underground stone masonry structure about 5.3 metres in height, has been confirmed to have been built between the eighth and ninth centuries while the second, a partly exposed stone wall 1.2 metres in width and 26.5 metres in length, is believed to have been used as a fort wall. 
    The third is a platform-like structure surrounded by a peripheral stone wall, encompassing a trapezoid surface, believed to have been used for rituals. But the archeologist is yet to relate the trapezoid shape to others in Bhutan. 
    Many pottery remains were unearthed inside the 2.8 by 2.5 metre chamber of the platform structure. At the bottom a possible painting on the mud floor was discovered but, Mr. Reto Blumer said, it had been preserved very badly.  
    The fourth structure is believed to be a tower foundation.  
    Last year Mr. Reto Blumer and his wife found remains of camp fires inside the first and second structures, proving that it was used by persons who probably had camps in and around the fortifications. They also discovered that after the use of the fortifications the structures were filled up with stones to make it difficult for any one else to use at a later stage. 
    The Swiss team has also managed to collect small broken pieces of pottery and a grinding stone that helped date the period of the structures. 
    Mr. Reto Blumer said it was hard to say exactly who had built the structures but, having dated to the 16th century, it was probably built by the local population who inhabited the area at the time. 
    The on-going excavation involves the SDC/Helvetas, the National Commission for Cultural Affairs, and the Swiss Liechtenstein Foundation. 
    More discoveries are expected.