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The subject of this drawing, continued on folio 32 recto opposite (D01514; Turner Bequest XL 30), has not been satisfactorily identified, but the mountains it depicts are likely to be the Brecon Beacons, seen from the banks of the Usk or the Taf. Compare the subject of folios 34 verso–35 recto (D01518–D01519; Turner Bequest XL 32a–33). The buildings glimpsed among trees on the far shore of the river seem to be a ruined manor house with prominent gable, and, beyond, a castle substantially preserved.
Another possibility is that the gable is one of those which form a distinctive feature of the Cyfarthfa ironworks at Merthyr Tydfil; see the contemporary Cyfarthfa sketchbook (Tate D01629; Turner Bequest XLI 1). However, the ironworks were not shrouded in trees as is suggested here.