The first mission was undertaken by Russians in the 17th century.
A major restoration was undertaken in the early 21st century.
A major revitalization of the Duluth downtown area was undertaken in the early 21st century.
A major restoration was undertaken in the 15th century.
It was first undertaken in the late 19th century by cooperating educational institutions.
For the village's further development, important measures were undertaken in the late 19th and early 20th century.
Major excavations were undertaken in the early 20th century.
Restorations were undertaken in the 9th century and ca 1080-99.
Further alterations were undertaken later in the 20th century.
The last rebuilding effort was undertaken by the Russian imperial authorities in the 19th century.