The mausoleum of Mammadbeyli or Yahya ibn Muhammad al-Hajj is located in the village of Mammadbeyli in Zangilan District of Azerbaijan.
[Azerbaijan Soviet Encyclopedia. Vol. VI, 1981, p. 493]
[Karabakh: history in the context of the conflict \\ Meshadikhanum Neymatova. [Epigraphic monuments of Karabakh. 2014, p. 140]

The mausoleum was erected on March 28 – April 27,1305 by an architect Ali Majd al-Din. This is confirmed by an Arabic-language handwriting inscription inserted above the entrance aperture of the mausoleum: “I am the owner of this building (i.e. buried in the mausoleum), a weak slave in need of the mercy of Allah the Most High, Yahya Ibn Muhammad al-Hajj. It was built by the hand (architect) of Ali Majd al-Din in the month of Ramadan in the year of 704 (28.III-27.IV.1305)”. At the beginning of the inscription and in the frame there are verses from the Koran.
[Karabakh: history in the context of the conflict \\ Meshadikhanum Neymatova. [Epigraphic monuments of Karabakh. 2014, p. 140]

According to Azerbaijani historian Meshadikhanum Neymatova, the son of a high-ranking government official, Muhammad al-Hajjah-Yahya, was buried in the mausoleum. However, the mausoleum and the village of the same name were mistakenly named after his father as “Mammadbeyli”.
[Karabakh: history in the context of the conflict \\ Meshadikhanum Neymatova. Epigraphic monuments of Karabakh. 2014, p. 141]

The mausoleum has an octagonal shape and is covered with a pyramidal dome. It was built of white stone, but the cornice was built of black stone. The main entrance to the mausoleum is from the northeast side.
[Azerbaijan Soviet Encyclopedia. Vol. VI, 1981, p. 493]
[Architecture of Azerbaijan. Essays. 1952, p. 264]

The dome of the mausoleum consists of two coverings: the outer one is in the form of a pyramidal tent and the inner one is spherical. The space between the inner dome and the outer tent is filled with lightweight aggregate.
[К. M. Mamedzadeh. The construction art of Azerbaijan (from ancient times to the XIX century.) 1983, p. 41]

In the book “The Construction art of Azerbaijan (from ancient times to the XIX century)”, 1983, the following is noted:
“Unlike other octagonal mausoleums, which have a low-height basement, here the entrance aperture is located at a height of 1.8 m from ground level. This feature and the presence of the crypt brings the mausoleum in the village of Mammadbeyli closer to the tower mausoleums of Azerbaijan.”
[К. M. Mamedzadeh. The construction art of Azerbaijan (from ancient times to the XIX century.) 1983, p. 40]

The mausoleum crypt was first identified in 1975, as a result of the complete cleaning of its underground part. It is a rectangle, measuring 2.95 x 3.30 m, at a height of 1.90 m and is covered with an ogive. The entrance to the crypt was arranged on the west side.
[К. M. Mamedzadeh. The construction art of Azerbaijan (from ancient times to the XIX century.) 1983, p. 41]

With the occupation of Zangilan by Armenian armed forces in 1993, the mausoleum was subjected to destruction.