The most important Greek sanctuaries, such as those at Delphi, Olympia, and Delos were all, to a large extent, excavated before archaeology was considered a primary source for knowledge of Greek cults and Greek religion. Therefore, the received picture of the Greek gods and of Greek religion is one based mainly on sources such as ancient literature, Greek vases, and sculpture.

The Poseidon Sanctuary on Kalaureia (Poros) was first excavated in 1894 by the Swedish scholars Samuel Wide and Lennart Kjellberg. Their objective was to uncover the foundations of the buildings, and to draw up plans of them, as well as plans of the sanctuary. Their actions were in accord with the standard archaeological practice of the time. In many cases the trenches they dug along the foundation walls can still be seen on the site. Excavations were resumed in 1997 under the direction of Berit Wells for the Swedish Institute at Athens. Between 2003 and 2005 Riksbankens Jubileumsfond financed a three-year programme entitled: Physical Environment and Daily Life in the Poseidon Sanctuary at Kalaureia, which was geared towards retrieving new data pertaining to the sanctuary through modern archaeological methods. Through analyses of organic residue in pottery, as well as analyses of charcoal, animal bones, seeds, mollusks, and metal slag, the traditional picture of sacrifices, dining, and construction in the Kalaureia Sanctuary, is slowly changing. A new picture of daily life in this large Greek sanctuary is now emerging instead.

Despite the wealth of new information that the excavations have so far provided, there is still much that remains to be discovered about the sanctuary at Kalaureia. For instance, we still do not know how large the sanctuary was; nor do we know how the sanctuary relates to the city. In all probability, the city is secondary and may not have existed before Hellenistic times, i.e. no earlier than the end of the 4th century BC. By that time the sanctuary had been in existence for over four hundred years. The current research programme entitled: , has a broad scope, and will employ new methods and theories, not only within the domain of classical archaeology, but also within those of religious studies and social anthropology.

The new programme will initially focus on field investigations of two monumental structures, whose properties have been defined by means of geophysical prospection. Both of them are located close to what is perceived as the border zone between the city and the sanctuary. As a result, a study of them may well contribute to knowledge of Kalaureian religion. The working hypothesis of the project is that the local religion was not static, but rather developed out of local, societal needs, and subsequently changed character when the historical situation so demanded . The prevalent hypothesis in research pertaining to Greek religion in general, however, is that it was closely associated with the growth of the polis or city-state, and its changing needs. Returning to the project at Kalaureia, the basic hypothesis pertaining to religion here is the contrary one to that of Greek religion in general, owing to the fact that the sanctuary came first, and then the polis. Indeed, a greater knowledge of the specificities of local religion will hopefully contribute to a greater knowledge of Greek religion as a whole.

For hundreds of years, people on the island of Poros, and the other islands in the Saronic Gulf, have plundered the sanctuary of its stones. Thus, it is primarily only the foundations of its buildings that remain, and, in the case of the temple of Poseidon, not a single stone lies in its original place. Yet before the blocks were removed they were cut to sizes appropriate for future use. For example, when a column drum was cut into a square block, the flutes were cut off, and many such architectural fragments have been retrieved from the 1894 excavation dumps. When measured and statistically analyzed, they can reveal column size and height. Also, a wealth of fragments from the terracotta roofs of buildings have been found. Together these find categories will be utilized digitally to reconstruct the original buildings.

A third objective will be to study which role, if any, the Poseidon Sanctuary has played for local identity in modern times. Both archival material, and field studies based on interviews with people either living on Poros, or just visiting the island, will be of importance here. Greece today is a country in the midst of great change. Like many small Greek communities, modern-day Poros has a heterogeneous population, consisting of native Greeks, asylum seekers, and economic refugees. In addition, there are thousands of tourists - many of them from Scandinavia - who visit the island every year. The importance of the ancient monuments for Greek national identity has long been taken for granted. However, exactly how the ancient ruins function, and have functioned, on a local level, in a growing multicultural society, has not previously been examined in depth.

The project is directed by Berit Wells and Arto Penttinen. The research group is an international one, and its members have different scholarly backgrounds. By means of dialogue a new and different picture is expected to emerge of how the Greek gods were used, both in the past, and in the present.