Haft Tanan Crypt (Museum of Historical  Stones)

Haft Tanan means "seven bodies", and the site is called so because of the seven tombs located in its courtyard. The tombs reportedly belong to seven dervishes. The identical tombstones, lacking any inscription, were installed in the middle of the courtyard during Karim Khan's rule. Six of them stretch in a row, while the seventh is placed behind them.

The north side of the compound at the foot of Mount Chehel Maqam contains a building with an open porch in the center, and chambers and arched recesses on the sides. The structure occupies an area of about 155 sq. m and rises 12 m high. The porch is supported by two monolithic columns, each formerly painted with detailed patterns; the remains of the paintings are still visible. The dados are overlaid with fine marble plates, while the walls and the ceiling are colored in blue and gold floral patterns. "The porch features five remarkable paintings executed by Aqa Sadeq, the renowned painter of the Zand age.

From left to right these portray - A dervish with a long, white beard, carrying a Kashkul and an ax, perhaps Sheikh Safi al-Din Ardebili; - Moses, shepherding a flock of sheep; - Sheikh Sanan, the famous Sufi character of Attar's mystic poem Manteq al-Teyr (“The Conference of the Birds"), who fell in love with a Christian girl; - Abraham sacrificing Ishmael (not Isaac, as in the Christian tradition); - A young dervish - there is disagreement as to whether he is Saadi or just an unknown Sufi.

The story goes that the Haft-Tanan structure was built by Karim Khan as a copy of his famous Divan-Khaneh. By this act, the ruler wanted to quench the public's curiosity about his ministry, the interior of which was accessible only to authorized personnel. The edifice is fronted by a pool, formerly filled by the water of the Roknabad qanat.
At present, the building houses the Museum of Stone, with prehistoric stone coffins, ancient tombstones, bases of Achaemenid stone columns from the Abu Nasr Palace, stone relics from the Sasanid to Qajar period, etc. on display.