Along the walls, starting from the north and moving clockwise, the following structures can be admired:
Porta Vecchia: the oldest city gate opens to the south corner of the walls and gives way to the old route of the Via Aurelia into the historical centre of town.
built in 1575 the polygonal bastion makes up the top south point of the walls, next to Porta Vecchia. The garden along the walk housed performances during the summer season at the beginning of the twentieth century.
Porta Corsica: opened along the south-west part of the walls during the last century, it connects the town-centre with the corresponding suburb area.
Bastione Molino a Vento: also built in the second half of the sixteenth century, it constitutes the top south-west point of the walls. Originally there was a windmill, hence the name. The garden with areas for cultivating citrus trees also boasts a characteristic nineteenth-century pond.
Bastione Garibaldi: realised in 1577, it constitutes the top north-west point of the walls. The name comes from the presence of a statue of Garibaldi. On this bastion in the 1930's a modern building was added that currently houses a dance-hall.
Porta Nuova: this constituted the second gate of entry to the centre, on the north side of the walls. A series of interventions carried out in the last two centuries saw first the demolition of the gate and part of the walls next to it, subsequently the collocation of a new gate in iron and cast iron, the 'Barriera di Porta Nuova', which was finally taken down definitively during the last century.
Bastione Rimembranza: built in 1577, it constitutes the top north point of the walls. During the last century the garden was transformed into a memorial park with a 'Monument to the Fallen' and a 'Monument to the Unknown Warrior' that took the place of the original ‘Polveriera’, a military structure designed for the safeguarding of ammunition and explosives. In the sixties some archaeological remains were placed here, creating a sort of park/museum.
Bastione Fortezza: an impressive pentagon-shaped complex that constitutes the top north-east part of the walls. Completed in 1593, it consists of Bastione della Vittoria, Bastione di Santa Lucia (facing inwards) and includes the 'Cassero Senese', 'Piazza d'Armi' and the 'Cappella di Santa Barbara' that made up the fortified citadel of Grosseto.
Bastione di Santa Lucia: a lesser bastion that constitutes the north-west part of the Bastione Fortezza. It contains the 'Cassero Senese' on the side facing the town-centre, and includes a series of embrasures and a perfectly conserved sentry-box called the 'Casino della Sentinella'. On the inner side it is made up of two lesser bastions, 'Bastione di Santa Lucia' facing north and 'Bastione di Vittoria' facing south.
Cassero Senese: of fourteenth-century origin it is one of the fortifications that made up the original Mediaeval city-walls. The double arch on the outer side containing the coat of arms of Siena is particularly characteristic.
Porta di Santa Lucia: built between the end of the thirteenth and beginning of the fourteenth centuries it opens near the Cassero Senese which was built shortly after. It originally opened along the east part of the Mediaeval walls.
Piazza d'Armi: a rectangular shape that opens up in the Bastione Fortezza. There are a series of sixteenth-century buildings overlooking the square, including the 'Cappella di Santa Barbara'. In the Piazza there is a well of the same period with an underground reservoir for the collection and conservation of water (see below).
Pozzo della Fortezza: a well-reservoir of octagonal shape built by the Medici in 1590, collocated in the centre of Piazza d'Armi. In the past, it collected rainwater that was purified and conserved in the spacious reservoir under the ground.
Cappella di Santa Barbara: sixteenth-century military chapel originally dedicated to Santa Lucia, it is incorporated into other buildings of the same period. Up to the mid-nineteenth century soldiers killed in battle were buried here.
Bastione Maiano: the oldest bastion, constructed in 1566 almost ten years before the Medicean renovation of the walls. It constitutes the top south-east part of the walls. Here used to stand the sentry-box, also named 'Casino delle Palle' (balls) because of the Medicean coat of arms it bore.