The palace complex of Mystras, where its administrative offices were housed, can be found overlooking the square of Ano Chora. The palace also served as the residence of the governor (kephale), and later, of the despots.
The L-shaped building has four construction phases covering the period from the thirteenth to the fifteenth centuries. The original core, a two-story structure with a tower, bears many Western features, such as pointed-arch windows, and was most likely built by the Franks before Mystras came under Byzantine control. During the era of Andronikos II, at the end of the thirteenth or beginning of the fourteenth century, the palace expanded toward the west with a two-story construction that followed Byzantine tradition. The arched window openings are semicircular. The next extension, also toward the west, was undertaken in the second half of the fourteenth century during the era of the despot Manuel Kantakouzenos. The two-story structure presents typological and architectural similarities with contemporary houses of Venice.
The last Byzantine building phase includes an impressive three-story elongated building on the northwest, which combines elements of Byzantine and Western architecture. It is attributed to the emperor Manuel II Palaiologos, who stayed in Mystras for long periods in the years 1408 and 1415. A magnificent throne room was located on the uppermost floor of this extension, with a balcony overlooking the square.
Photos and Plan from Millet
Oxford Dictionary of Byzantium
Mistra, A Fortified Late Byzantine Settlement by Sophia Kalopissi-Verti
Les monuments byzantins de Mistra by Gabriel Millet