Crochendy Twrog is part of the former estate farm for the Plas Tan-y-Bwlch Estate. It dates from c1830, but was probably extended in the mid-nineteenth century. It comprises a number of now-converted farm buildings, built from very long blocks of stone laid un rough course under slate roofs, and forming a courtyard entered through an archway with living quarters over and a bellcote. The buildings include a four-stall stable with hay-loft over, a tack room with some surviving features, cattle sheds with fourteen stalls divided by heavy oak partitions, and a milking parlour with brick floor and ceramic feed troughs. On the south-east side there is a three-bay cart shed with bothies at each end, and a weighbridge house with a standard made by Robert Melvin of Alloa, Scotland.

The north corner of the complex is an open-sided haybarn with a half-hipped roof supported on tall, monolithic stone columns, aligned to the south-west with a two-storey building which is said to have been built as a corn mill, but then became a workshop. It was powered by a turbine, no longer in situ; there is a sack hoist trap to the loft and a single lineshaft, but no other evidence of it having been a mill. At the west corner is a two-storey dwelling, and detached from this is an octagonal building built of firebrick, its interior white tiled and lined with pitch-pine, with a boarded roof. Over this is a second, slated octagonal roof, its eaves supported on tall monolithic stone columns. Well-finished horizontal pine timbers bridge across between the columns, forming an eight-sided cross at the centre, from which a central post supports both roofs. This building is now known as the "buttery" and may have been a dairy or meat store.

The haybarn and the former mill/workshop are separately Listed Grade II (Ref. No 25065 and 25436).

Information from Cadw Listed Buildings database.
W J Crompton, RCAHMW, 22 May 2014.