Napoleonstein

Founded in 1926 using Carl Zeiss technology, it is one of the oldest projection planetariums in the world. There are educational programmes, entertaining programmes for families, music shows and film screenings.

Second-oldest and one of the most famous and most beautiful botanical gardens in Germany.

Gothic gate tower, another—much better preserved—part of the medieval fortifactions. It is linked with the nearby magazine (Pulverturm) by a reconstructed wall walk.

144.5-m-high office tower built in the early 1970s for the university and intended by the communist rulers to be a dominant part of the "socialist city". It was designed by Hermann Henselmann (architect of the Berlin television tower) to remind of an upright telescope (alluding to Jena's optical industries). It was renovated and modernised around 2000, receiving its characteristic glass façade. Main tenant of offices is the e-commerce developer Intershop. There is a restaurant on the highest floor and an observation platform on the top.

Comprehensive exhibition illustrating the development of optical instruments and technology through the ages, focusing on the work of physicist Ernst Abbe and entrepreneurs Carl Zeiss and Otto Schott and their respective companies. English-language guides available by prior appointment (€40 for the whole group), audioguides in English, French, German, Italian and Japanese (€1 per person plus €5 deposit).

Main Protestant parish church of the city. There probably was a church at this location as early as in the 12th century. The present building was started around 1380 and is a late-Gothic hall church. The 75-metre-high octagonal tower is topped by a Renaissance-style crest. An architectural anomaly is the underpass below the church's sanctuary and altar that served as the only passage to the (long disbanded) Cistercian convent behind the church during medieval and early modern times and was considered one of the "Seven Wonders" of Jena.