Systematic archaeological research of Dubingiai castle site, located on a peninsula (formerly an island) in Lake Asveja, began in 2003. In 2004, at the site of the former church, the remains of members of the Radziwiłł family were discovered and identified through the combined efforts of archaeologists, anthropologists, historians, and art historians. Laid to eternal rest here were Mikołaj Radziwiłł the Black (1515–1565) and his wife Elżbieta Szydłowiecka-Radziwiłł (1533–1562); Mikołaj Radziwiłł the Red (1512–1584), his eldest son Mikołaj Radziwiłł (c. 1546–1589), his grandson Janusz VI Radziwiłł (1579–1620), and daughter-in-law Anna Sobkówna-Radziwiłł (d. 1578), the first wife of Krzysztof Radziwiłł Piorun (“the Thunderbolt”),
Between 2006 and 2008, the entire site of the former churches was thoroughly investigated. The foundations of the Evangelical Reformed Church were restored, preserved, and adapted for visitors. A new burial crypt for the Radziwiłł family was constructed, along with an ornate new sarcophagus for their remains and a granite tombstone bearing an epitaph. On September 5, 2009, the discovered and identified remains of the Radziwiłł family members were solemnly reinterred in the newly prepared crypt.
Alongside the research of the former church in the Dubingiai castle site, archaeological excavations were also carried out in the territory where the Radziwiłł Palace once stood. Investigations of the palace remains began in 2005, with the most extensive work taking place in 2008–2009, when the former Radziwiłł Palace was uncovered. It was determined that the building of the palace consisted of two main parts: an earlier eastern section from the early 16th century, which included two cellars and partially preserved first-floor pavements, and a western section added in the early 17th century, containing two rooms divided into anterooms and halls.
In 2012, a museum was opened at Dubingiai castle site. A special modern concrete structure with a grass-covered roof was built over the uncovered palace remains.
