This is the Muradiye mosque, by the greatest Turkish architect, Sinan. It is one of his last works, from 1582-1585, who built it for Murat III.

An entrance on the west side.

Architect: Mimar Sinan, by proxy, but he may have visited the site on his return from the Pilgrimage to Mecca.
His first deputy, Mahmut Ağa, died and was succeeded by Mehmet Ağa, who later built the complex of Ahmet I (the ‘Blue Mosque’ and its annexes) in Istanbul.

Correspondent: J.M.Criel, Antwerpen.
Sources: ‘Islamic Architecture: Ottoman Turkey’ (Godfrey Goodwin) – London 1977
& Website of ‘Manisa Il Kültür ve Turizm Müdürlüğü’ .