Canvas Print of This is the view across the Tywi estuary and Cefn Sidan Sands from the castle at Llansteffan Carmarthenshire. Llansteffan Castle offers free entry and is well worth a visit. The view is of the Carmarthenshire coast. Llansteffan is across the river from Ferryside and the castle clearly visible. Because of this the journey to Llansteffan is a long one from Ferryside!