what is its architectural structure like?
It is situated on a rectangular plot and is two stories tall
Al-Masjid an-Nabawi
The modern-day Masjid an-Nabawi is situated on a rectangular plot and is two stories tall. 
who is the current imam of masjid nabawi UNANSWERABLE what happened during its first expansion? The mosque was expanded on each side and three rows of columns were built beside the west wall, which became the place of praying when did the saudis invade here? 1805 what did they do during their insurgence? They demolished nearly every tomb and dome in Medina in order to prevent their veneration
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Al-Masjid an-Nabawi [SEP] Architecture
The modern-day Masjid an-Nabawi is situated on a rectangular plot and is two stories tall. The Ottoman prayer hall, which is the oldest part of Masjid an-Nabawi, lies towards the south. It has a flat paved roof topped with 27 sliding domes on square bases. Holes pierced into the base of each dome illuminate the interior when the domes are closed. The sliding roof is closed during the afternoon prayer (Dhuhr) to protect the visitors. When the domes slide out on metal tracks to shade areas of the roof, they create light wells for the prayer hall. At these times, the courtyard of the Ottoman mosque is also shaded with umbrellas affixed to freestanding columns.