the 1330 Arburghaus which was destroyed in the fire. Above the doorway is a plaque dated 1596 combining the coats of arms of the Empire, the Canton of Bern and the von Erlach family, and naming Anthoni von Erlach as Landvogt. To the east of the gatehouse stands the north keep, since the complete rebuilding of 1718–20 connected to the adjacent buildings. The gatehouse and dungeons were once located here. Of the original building only the west wall and parts of the foundation of the south and east walls remain. The new Landvogt's residence was built in 1672–74 on the site of a 1625 guardhouse and laundry. The neighbouring Landvogtei at the northeast corner was at the time no longer inhabitable because of penetration of the walls by damp following the construction of the east bastion. Today the administrative centre of the Aargau Museum is located here. Landvogt's residence The three-storey late Gothic Landvogtei with its stepped gable was built in 1520. It served as a new office and residence for the Bernese Landvögte after the destruction of the previous building dating to the 14th century in a fire in 1518. In contrast to the other buildings, the Landvogt's residence does not back directly up to the ring wall, but is separated from it by a 1 to 2-metre gap. The exception is a small round tower at the southeast corner; built in 1626, it replaced a protruding bay that served as an outhouse. The pentagonal stairway tower which was attached to the façade in 1630 replaced a steep staircase within the building. Its original onion dome was replaced with a hip roof in 1760. The foyer still dates back in part to around 1460. On the first upper floor a gallery, constructed in 1565, extends the length of the north side. From 1646 until 1894, the building was uninhabitable because of encroachment of damp after the construction of the east bastion. Renovation was only possible after the removal of the embankment in 1902. The renovation included a new façade facing the inner bailey. Today the building houses part of the Aargau Museum, with a permanent exhibit on the lives of the castle owners from the late Middle Ages until the 20th century. East bastion The bastion on the eastern perimeter of the inner bailey was constructed in 1642–46, replacing a curtain wall with battlements, to close the gap between