Rhosybreidden (or Rhosybreiddin) is a smallholding built in the 17th or 18th century,on or adjoining the common of the same name. It was enlarged and extended in the 19th century. It lies in Dolwar township in the parish of Llanfihangel yng Ngwynfa, halfway between Dolanog and Pont Llogel close to the River Vyrnwy.

It was purchased by Wynnstay estate in 1839. It was also named in parish and census records as Castell Breidden and Britten cottage. The tenants from about 1839 to about 1920 was the Storer family. John Storer (1824-1899) and his son Joseph Storer (1874-1967) were district surveyors for Llanfyllin council.

In 1946 the house was purchased from the Wynnstay estate by the tenants William and Jane Jones and sold to the Church family in 1964, who remain the owners and occupiers.