Over the years Birka and Hovgården have been the subject of a series of exciting excavations. Hjalmar Stolpe examined many of the graves in the large grave-field during the 19th century and also dug an exploration shaft in the area referred to as the Black Earth. Björn Ambrosiani further investigated the Black Earth and the trading port in the early 1990s, and in the late 1990s Stockholm University examined an area outside the town wall.

A number of marine archaeological investigations of the port and the waters around Birka have been done in more recent years. Archaeologists from the Swedish National Heritage Board did investigations of the Björkö village community between 2005 and 2007, and in May 2008 Södertörn Högskola was responsible for a seminar to excavate of the Black Earth at the waters edge. A multitude of findings by archaeologists over the years have given us a more thorough and consistent picture of life on Birka, but a lot of archaeological work remains to be done.

An area outside the old town site is called "the garrison". This is the focus for much of the archaeologists' attention in recent years. A variety of weapons were discovered already in the 1930s: arrows, spearheads, knives and parts of shields. Parts of an iron armour was a particularly noteworthy finding. The iron armours were difficult to make and very valuable. The garrison is the only place in all of Scandinavia where such parts of armour have been found.

Professional army

Excavation results suggest there was a well-equipped army of professional soldiers on Birka. Nineteen metres long, the imposing Warriors' House is the largest building on Birka. It was probably used as an assembly hall for Birka's warriors during festivities and ceremonies. Spearheads, parts of shields and remains of coffers were found along the walls. One exciting finding was a small dragon's head in bronze. House sacrifices, which were holes in the ground where objects were sacrificed to protect the building and its residents, were also uncovered. In the Warriors' House two Islamic coins and an ornamental hammer of Thor had been sacrificed.

The foundry of war

Archeologist paid close interest in the remains of a foundry near the Warriors' House during the 2002 excavations. Some of the close to 500 discoveries are remarkable and connected to the hall: such as knives, hammers of Thor and tools. Five oriental belt-buckles are especially interesting, as they reflect Birka's trade relationship with the Kiev empire and Byzantium.

New discoveries in Björkö Bay

Diving expeditions offshore of Birka have also produced many interesting discoveries. There is a puzzling pile of boulders in Björkö Bay, for example, which could have been arranged to prevent invaders from entering the harbour. Marine archaeologists have also discovered remains of a 300-meter long palisade of poles outside the dock. The bottom of Lake Mälaren around the Björkö island was searched for the first time with an advanced sonic-depth finder during the summer of 2002 and more than a hundred previously unknown artifacts were detected. Several shipwrecks, old and new, were found. Diving expeditions around the wrecks are planned in order to establish the age of the findings. Maybe an old Viking ship is buried in the mud beneath the dark lake!

The town centre and the dock district

Archaeologists excavated the town centre and the beach during the first half of the 1990s. Ruins of a bronze foundry was one of the finding. The archeologists were delighted to learn that the molds fit perfectly with artifacts detected one hundred years ago during excavations of Birka's burial site.