One of Seggiano's main attractions is the Olivo nel Cisternone, a scientific installation that represents not only a prime example of the Olivastra seggianese cultivar, but is also the largest plant in the world to be sustained by aeroponic technology. The roots of the plant are suspended inside what used to be the town's water cistern, and are fed by water vapour and vaporized nutrients. The installation makes up part of a larger project started in collaboration with neurobiologist Stefano Mancuso, who is known the world over for his studies on the intelligence of vegetable life.
The suspended olive tree is also the starting point for a walk around the Olive Oil Museum, a "diffused museum" that winds through the town centre. Among the many stops along the trail, it is most definitely worth visiting the old olive press and oil house, where you can take part in a Seggianese DOP tasting session.
A stroll around the town also takes you to the neogothic town hall, where the parish church of San Bartolomeo spears the sky. Originally built in the Middle Ages and rebuilt in the 1930s, the church is home to a polyptych of the Madonna and Child enthroned with St Bartholomew, St Michael and St John the Baptist. Further along, you will find the church of Corpus Domini, which is dedicated not only to the Body of Christ but also to St Bernardino of Siena. Here you will find a Madonna and Child from the late fourteenth century and a reliquary that belonged to St Bernardino himself.