The first archaeological exploration of the site happened around the early 1930s by an American mission.

Archaeological exploration of the area began in the nineteenth century.

The first archaeological explorations were carried out in 1936 and 1938.

The historical settlements in the area have been subject of archaeological exploration.

Large sites in the devastated city center have now been opened to archaeological exploration.

Archaeological exploration led to a realization that rice had been grown in the area for more than 2000 years.

At the same time he conducted several underwater archaeological explorations.

The country abounds in other sites that are difficult to reach and have seen little archaeological exploration.

Archaeological exploration, to determine the exact fort site, would be desirable.

Nevertheless, systematic archaeological exploration did not begin until 1928.