 St Nidan 's Church was built between 1839 and 1843 , replacing its medieval predecessor . The architect was John Welch , who also designed St Ffinan 's Church , Llanffinan , in central Anglesey , which was built in 1841 . St Nidan 's was originally intended to have a spire on the west tower , but this was not added . The chancel was built in 1882 , and a vestry and organ chamber added later . The battlements on the tower were added in 1933 , replacing the original <unk> . St Nidan 's is set within a walled churchyard on the north of the <unk> road , in the south of Anglesey , Wales . The village of Brynsiencyn is about 500 metres ( about one @-@ third of a mile ) to the south @-@ west , and the old church of St Nidan is about 750 metres ( about half a mile ) to the south @-@ east . 
