Research of the Old town cultural layer, publication of research data, collection of archaeological findings and their scientific analysis is one of Kėdainiai Regional Museum scientific activities fields.
The cultural layer of Kėdainiai Old town is being excavated since 1986. Throughout the twenty years, an area of about 3 hectares of the 87 is researched. The area is the Old town and has a status of national monument.
Researches of the Old town cultural layer have not only cognitive importance, but also practical value. Uncovered boundaries of vanished plots, remains of buildings and cellars, cobbles of streets and squares provide important data for preparing regeneration projects of the Old town quarters and particular plots, restoring old and constructing new buildings.
During excavations of particular areas of the Old town, researchers not only estimate a thickness and constitution of a cultural layer, its extent or formation throughout more than 600 years, a period of Kėdainiai town existence, but also fix and research constitution and structure of natural layers, what were formed in a valley of the Nevėžis River and its upper terraces. Such researches let estimate a conformation of Kėdainiai terrain before people settled there and answer a question, when people settled in the area of the present Kėdainiai and why they chose that area of the Nevėžis valley.
The cultural layer of the Old town is one of the main sources, what helps to know better the historical development of Kėdainiai, household and culture of people, who lived there. The research data of the cultural layer are greatly important in estimating rise of Kėdainiai, its primary build-up, planning of plots and problems of the town dwellers.
From 1986 till 1990 Kėdainiai Old town was researched by excavations of exploratory character, but since 1990 researches of a larger extent have been started: in 1990 – 1991 after exploring of an area of 688 m2 in the southern corner of the Old Market Square, remains of stone and wooden buildings the 16th-19th c. were uncovered; in 1992 after exploring of an area of 985 m2 in a corner of Radvilų and Skongalio streets, fragments of a wooden settlement of the 14th-15th c. were uncovered, in 1992 – 1998, plots alongside the main streets of the Old town were researched estimating their size and character of a build-up.
Monuments of architecture of Kėdainiai Old town have been researched since 1999. In 1999 a research of Kėdainiai Gymnasium Illustrum of the 17th-19th c. had been carried out, in 2002 – 2003 there were researches of buildings of synagogues’ complex of the 18th-19th c., in 1998 and 2004 – researches of houses of the Scots Stigley and Arnet. The data of the archaeological researches had been applied in restoration of the buildings.