 Arba 'a Rukun Mosque is one of the oldest Islamic places of worship in the capital . It was built circa 667 ( 1268 / 9 AD ) , concurrently with the <unk> ad @-@ Din Mosque . Arba 'a Rukun 's <unk> contains an inscription dated from the same year , which commemorates the masjid 's late founder , <unk> ibn <unk> al @-@ <unk> ( <unk> ibn Muhammed ) . 
