The presumption must be that this drawing shows Dolbadarn Castle, as do several others in this book: folios 21 recto, 38 verso–39 recto, 41 recto opposite, and 44 recto (D02026, D02049–D02050, D02054, D02060). However, the tower here appears to be square, and in other respects as well bears a closer resemblance to the keep of Dolwyddelan Castle than to Dolbadarn. Dolwyddelan is situated above the valley of the Lledr, north of Blaenau Ffestiniog, and south of Moel Siabod, in a different part of Snowdonia not immediately accessible from Llanberis.
If this is indeed Dolbadarn, Turner has again, as in D02049–D02050, adapted the landscape into a composition of his own. The spur of land on which Dolbadarn sits is higher than indicated here, though not as cliff-like as in that drawing. Compare also D02060, which again exaggerates the height of the spur, but in the context of a drawing that is more obviously a composition study rather than a sketch from the motif.