The mosque:

The mosque consists of two blocks, both measuring 42 m square: a domed prayer hall fronted by an enclosed courtyard. The mosque is accessible from the north, south, and west via five primary entrances: three portals open into its front courtyard and two into the prayer hall. The qibla wall forms the eastern elevation of the mosque.

The courtyard is surrounded by a row of vaulted portico bays accented with white and pink marble voussoirs. The courtyard is notable as the first example in Ottoman architecture of the use of an open-air portico, instead of enclosed galleries, as the surround for a mosque courtyard. The octagonal marble ablution fountain in the center of the courtyard was donated after the original construction of the complex by Sultan Murat IV (1612-1640/1021-1050 AH). At the center of the east wall of the courtyard is a recessed portal leading into the prayer hall, topped by elaborate carved muqarnas. 

The mosque's two minarets rise above the northeast and southeast corners of the courtyard. The enclosed stairways of the minarets are accessed from small portals on the exterior of the mosque. The shafts of the twin minarets feature ornate decorative sculpture in the form of geometric bas-reliefs and inlaid terracotta panels.

The prayer hall features a symmetrical, centrally focused plan, as did many of Sinan's mosques. Just as in the portico to the west, the plan of the hall is organized according to a five aisle by five row grid, in which domed bays along the perimeter form a square border around a larger three bay by three bay space at the center. The corner bays are each slightly under eight meters square, while the bays along the center of each wall are approximately twenty-two meters long and eight meters deep. Four massive pillars are located at the corners of the large central bay, whose interior spans nineteen meters square. The pillars each measure close to five meters square to provide support for the massive arches that frame the edges of the central bay. These four arches are flanked by semi-domes that cover the central bays along each wall of the prayer hall. The four arches also provide support for a nineteen-meter-wide dome that springs from pendentives over the center of the prayer hall. The central dome rises to a maximum height of thirty-seven meters, suggesting a spherical space in section. Three-meter-deep galleries line the exteriors of the north and south walls to conceal large buttresses that provide additional structural support for the heavy central dome.

The interior of the mosque features simple but fine decoration. The interior is primarily of white stone, with polychrome Iznik tile work in radial geometric patterns at the centers of each dome and semi-dome of the ceiling, as well as within triangular panels on the squinches and pendentives. The voussoirs are finished in a pattern of alternating red and white stones to draw attention to the large arches supporting the roof. A large circular iron chandelier is suspended from the central dome above the red carpeted floor. The mihrab niche is surmounted by muqarnas and surrounded by large stained-glass windows.

Entrances to the prayer hall are located at the center of its north, west, and south walls, while the mihrab niche occupies the center of the east qibla wall. The minbar is located four meters to the south of the mihrab niche along the qibla wall. As the four pillars at the center of the support much of the load of the domed roof structure, the exterior walls have relatively little load to bear and thus are highly perforated to allow generous sunlight. Sinan revised this simple plan in his later imperial mosques to allow the support piers to be better integrated with the exterior walls of the prayer hall and thus less isolated near its center.

The mausolea:

The six mausolea are grouped to the southeast of the mosque, behind its qibla wall. The mausoleum of Şehzade Mehmed was the first structure constructed under Sinan's master plan for the complex. Measuring five meters to a side, the octagonal mausoleum is best known for its opulent decoration in polychrome Iznik tiles. Tiles in rare shades of green and yellow cover the entire interior of the space, including the floors and ceiling. The structure is supported by terracotta arches and roofed by a fluted dome. The tomb of Şehzade Mehmed is located at the center of the mausoleum, covered by a walnut baldachin. The tombs of Mehmed's daughter Humusah Sultan and his brother Cihangir are also located within the structure. Openings in the walls allow for stained glass windows on all faces, as well as an entrance portal on the north elevation. A porch featuring inlaid opus sectile stonework leads to the entrance portal, which is surmounted by a commemorative inscription in Persian verse.

Also designed by Sinan, the mausoleum of Rüstem Paşa (d. 1561/968) is located two meters south of Mehmed's mausoleum. Like the mosque of Rüstem Paşa in Istanbul, the octagonal mausoleum features elaborate Iznik tile work. The mausoleum of Şehzade Mahmud (d. 1603/1012 AH), located five meters to the southwest of Şehzade Mehmed's structure, is a hexagonal structure measuring three meters to a side. Immediately to its south is the slightly smaller octagonal mausoleum of  Şehhülislam Bostanzade Mehmed (d. 1598/1007 AH). Nine meters to the west, a larger octagonal mausoleum measuring four meters to a side honors Ibrahim Paşa (d. 1603/1012 AH). Designed by Dalgiç Ahmed Çavuş, this mausoleum is almost as large as that of Şehzade Mehmed. Finally, the baldachin tomb of Şehzade Mehmed's granddaughter Fatma Sultan (d. 1588-1589/996-997 AH) is located ten meters to the east of Mehmed's mausoleum. This small domed square structure measures four meters to a side and is located adjacent to the eastern wall of the complex.

The madrasa:

The madrasa is located thirty-seven meters north of the mosque at the northwest corner of the complex, along the northern wall of the enclosure. It follows a typical Ottoman organization in which twenty small cells and a second row of vaulted galleries are organized around a large rectangular central courtyard. Overall, the madrasa measures forty-six meters wide east to west and thirty-two meters long north to south. Its regularity is broken by a square domed prayer room embedded at the center of the eastern wall. This prayer room measures eleven meters to a side, and it projects five meters beyond the line of the exterior wall. The madrasa is accessible from the north via several entrances facing the Valens aqueduct, or by three central entrances along its south wall that face the mosque and mausolea within the Şehzade complex. 

The tabhane-caravanserai:

Though tabhanes were often directly attached to mosques later in Ottoman period, the tabhane at the Şehzade complex is a freestanding structure combined with a caravanserai located to the east of the madrasa and north of the mosque, along the northern enclosure wall. The building is composed of a series of domed chambers designed to house pious travelers during short visits to the mosque. It is subdivided into three sections; the western and central sections are identical, while the larger eastern section features a unique interior organization and an adjacent trapezoidal courtyard. The enclosed portion of the eastern section is composed of two aisles of domed bays, each four rows deep. The sections to the west are each subdivided into thirds, with two small domed chambers to both the east and west of a larger central domed space. The tabhane measures between sixty-two and sixty-seven meters wide east to west and between thirteen and twenty-four meters long north to south.

The hospice and elementary school:

The complex is interrupted by Dede Efendi Street to the east of the tabhane and mausolea, and though the complex's perimeter wall creates a solid boundary along the street-edge, a hospice and elementary school affiliated with the mosque were constructed directly across the narrow street. The hospice is rectangular with a large central courtyard, measuring approximately twenty-five meters wide east to west and fifty-six meters long north to south. The elementary school is located adjacent and to the south of the hospice, a small square domed structure measuring ten meters to a side. Opposite the elementary school, a small break in the complex perimeter wall allows entry to the gardens north of the mausolea. There is a second entrance opening to the courtyard of the tabhane, opposite the entrance to the hospice. The perimeter wall is further perforated to the east and south of the mausolea and to the south and west of the mosque in order to permit diverse points of entry to the complex, with no apparent primary gateway.

The Şehzade Mehmed complex is widely regarded as Sinan's first masterpiece. The simple design of its mosque foreshadowed both Sinan's later experimentation with geometrically rational spaces and his refinement of innovative structural systems. Its mausolea are well-preserved examples of the opulent decorative tile work reserved for only the most important imperial building commissions. The complex remains open to the public today as an example of Sinan's early vision and one of the finest architectural achievements of the Ottoman period.

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