The domed three-aisle basilica dedicated to the Annunciation of Theotokos is characterised as the centre and heart of the Holy Metropolis of Phthiotis. Its foundations were laid in 1861 and it houses many icons from the 19th century A.D., as well as a rich library full of information on the city of Lamia and its social events. Decorated with hagiographies by Nikolaos Rizos, it holds a wealth of wood reliefs and mosaics.