The Fortresses of Nisa are located in present-day Turkmenistan, and are the remains of a series of ancient Parthian fortresses that date back to the 3rd century BC. The fortresses were built by the Parthian Empire, which was based in modern-day Iran and Iraq, and they were used as a military base and administrative center for the region.

The fortresses consist of several large buildings and structures, including a royal palace, a temple, and several defensive walls and towers. The buildings were constructed using a combination of mud brick and stone, and some of the walls are several meters thick.

The site was rediscovered in the early 20th century, and extensive excavations have been carried out since then. Many of the artifacts that have been uncovered are now housed in museums in Ashgabat, the capital city of Turkmenistan.

In recognition of their historical and cultural significance, the Fortresses of Nisa were designated a UNESCO World Heritage Site in 2007. The site is open to visitors, and offers a unique glimpse into the history of one of the ancient world's most powerful empires.