The „St. Nikolai“ church is located in our town's cemetery outside the historic town center. The beginnings of the church go back to the time when the Ludovingian landgraves took possession of Tennstedt around 1130 and expanded the town. A „St. Nikolai“ chapel was first mentioned around 1550 in the church register of the church of St. Wigberti - today „St. Trinitatis“ or Trinitatis Church. According to the record, this chapel was built from the stones of the St. Severi church, which was located on the Österberg in the east of the city and was demolished.

In 1641, the chapel was enlarged and a new bell was cast. The bell came from the Jacob König bell foundry in Erfurt and hung in the church bell tower until it was demolished. In 1685, a devastating fire raged through the town and the church fell victim to it. Reconstruction of the destroyed building began in 1685 and was completed around 1700. The reconstructed building is a hall church with a five-sided choir. During this construction phase, the windows in the north wall were bricked up. However, the round-arched window walls have been preserved. The galleries and their supports were installed from 1820. In 1895, the church was given a rectangular west portal. In the 20th century, the church began its gradual decline, which reached its sad climax in the 1970s with the bricking up of the north portal, the dismantling of the bell tower and the closure of the church by the building authorities. In order to prevent the complete collapse of the church, extensive safety measures were carried out between 1993 and 1999. The historic roof truss was professionally renovated and re-roofed.

After that, the church was no longer accessible to the public for another 11 years. However, seven citizens of our town founded the „St. Trinitatis“ Bad Tennstedt e.V. support association and began renovating the church with great dedication in 2010. After just 8 months, the interior of the church shone in new splendor. The members of the association also built the wooden staircase in the south of the church in 2011. On September 14, 2011, the Gottesackerkirche was rededicated in an ecumenical service.

„St. Nikolai“ is used by the local population for church services, funerals and, thanks to its excellent acoustics, also for concerts.