Degenfeld-Schonburg mansion in Ács, Manor house ruins in Ács, Hungary.

The Degenfeld-Schonburg mansion is a one-storey historicist manor with neo-Renaissance elements, built in 1863 and standing southeast of Ács town centre in the Concóhát area. Its main facade has a 2+3+2 axis layout, an open porch with a terrace above it, and a slightly projecting central risalit. Two flat-roofed, single-storey wings were added on either side after the estate was bought by Count Ottó Degenfeld-Schonburg. The upper floor slab has largely collapsed, the staircase railing has been cut out, and doors and windows were removed with their frames.

The manor was built in 1863 by the Forster family and passed to Count Otto Degenfeld-Schonburg in 1900, who significantly expanded it. After nationalization in 1947, the building served various agricultural purposes and was partly converted into residential apartments.

Local tradition holds that the park was laid out on the orders of Queen Maria Theresa and became known as the Herkályi woods. The estate took its name from the Concó stream, and the chestnut avenue leading to the mansion survives in part. The building later housed several families as flats.

The site is accessible via asphalt roads, but entering the decaying building is unsafe and should be avoided. The best time to photograph and view it is from outside when the surrounding fields are not overgrown and the facade is clearly visible.

Local tradition holds that the park was laid out on the orders of Queen Maria Theresa and became known as the Herkályi woods. The chestnut avenue leading to the mansion survives only in part, alongside poplars, black pines, maples and oaks.