The Takht-e Foulad (Persian: تخت فولاد), also known as Lissanul Arz (Persian: لسان‌الارض), is a historical, predominately Islamic, cemetery located in Esfahan, in the province of Isfahan, Iran. It is a large funerary complex that includes several historic mausoleums, mosques, tekyehs, sub-cemeteries and standalone graves. It is estimated that the cemetery was established in c. 10th century CE and is noted for its Safavid architecture.

The cemetery was added to the Iran National Heritage List on 15 June 1996 and is administered by the Cultural Heritage, Handicrafts and Tourism Organization of Iran.

The exact origins of the cemetery are not known, but some historians have theorised that it may have pre-Islamic origins. During the rule of the Mongol Ilkhanate in the 14th century, the mausoleum of Baba Rokneddin Shirazi was built, and the cemetery was named after him. The cemetery subsequently became a place for Sufi dervishes to have mystical gatherings.

The cemetery was expanded during the Safavid era, under the rule of Shah Suleiman I. But later on during the rule of the Safavid Shah Soltan Hoseyn, many of the mausoleums from the Ilkhanid era were demolished, under the orders of Mohammad-Baqer Majlesi, the Shaykh-ol Islam hired by the ruler. The Sufis and their dervishes were also banned from visiting the cemetery, regardless whether they were Shi'ite or not. During the rule of Nader Shah Afshar, the cemetery was largely ignored, save for a small number of burials.

During the Qajar era, Fath-Ali Shah Qajar built a takyeh in the cemetery, which he dedicated to his mother. In the 20th century, however, Mass'oud Mirza Zell-e Soltan, the Qajar prince who governed Isfahan, demolished several Safavid-era structures in the cemetery. Later on, in the 1980s, a sub-cemetery was established around the grave of cleric Abolhassan Shamsabadi, and in the cemetery were buried those who were killed in the Haft-e Tir Bombing and the Iranian Revolution.

During the Pahlavi era, the cemetery had become full. Locals were then forbidden from carrying out any further burials. They were still allowed to visit the sites in the cemetery, however.

Baba Rukn al-Din, or Baba Rokneddin, was one of the most prominent Persian Sufis of the 14th century. He died in 1367, and the mausoleum was built during the Ilkhanid era. It had fallen into disrepair later on and was restored during the Safavid era under Shah Abbas I. It is the only structure from the Ilkhanid era to survive till modern day.

One of the takyeh buildings located in the cemetery. Clerics belonging to the Khatoon Abadi family are buried in there, an example being Mohammed Hossein Khatunabadi, a Shi'ite Hadith scholar. There is a small cellar underneath the tomb, speculated to be a place where the ascetic-inclined Khatunabadi secluded himself and meditated.