Columbia subject headings:
Harvard subject headings:
Altreu (Switzerland)--Antiquities.
Cities and towns--Switzerland--Altreu--History--To 1500.
Fortification--Switzerland--Altreu--History--To 1500.
Middle Ages
Solothurn (Switzerland : Canton)--Antiquities.
Princeton subject headings:
Altreu (Switzerland)--Antiquities.
Archaeology, Medieval--Switzerland--Altreu.
Excavations (Archaeology)--Switzerland--Altreu.
Extinct cities--Switzerland--Solothurn (Canton)