Segesta is the site of an ancient Graeco-Roman city. The site is immediately off the main A29 road, straight after a long tunnel if travelling from Palermo. Onsite there is free parking. Tarantola Bus goes between Palermo and Calatafimi (aka Calatafimi-Segesta) a few times daily, stopping at Segesta en route. You may have a long wait for a return bus. (Perhaps confusingly, Segesta Bus does not go to Segesta.) Coffee and pizza are available at the cafe near the car park.
Built between 430-420 BCE, 61 m (190 feet) long, 26 m wide, built upon a platform of 4 steps, it has 36 Doric columns supporting the stone roof-frame of the structure (14 columns along the lengths of the building, 6 columns across front and back). They are of a "rough" finish as the temple has never been completed. The temple seems also to have lacked a roof over the cella (main chamber) in antiquity, rather uniquely - scholars are in disagreement as to whether the temple was planned this way, or just never completed.
It is on a hilltop and was built by the Greeks at about 400 BC. It was discovered in the 19th century. They play classical comedies and tragedies in July and August. A bus (€1.50) is available every 30 minutes to the site of the Amphitheatre at the top of the hill. It's a brisk, uphill, 20-minute walk otherwise.
Colle pianto Romano
The Ossuary of Pianto Romano, built in memory of the soldiers who died in the battle between the Mille and the Bourbon troops, from a design made by E. Basile. It was inaugurated on 15 May 1892. From its top you can admire wonderful landscapes in all directions.
It is on a hill dominating the whole town. It is probably a 12th-century reconstruction of an older castle built for defence. Today there remain only a tower, some warehouses, the cells and the courtyard.
Chiesa di san Silvestro papa
This church was built in the first half of the 13th century and dedicated to Saint Silvestro the Pope; it was then rebuilt in 1547. It has a nave and two aisles, with Roman arches. There are a lot of stuccoes, paintings, marbles and wooden statues.
Church of the Most Holy Crucifix
This church was built at about 1750, to G.B. Amico's plan. In the façade there is a portal coming from the former church of Stimmate (Stigmata) in Palermo. Inside you can see frescoes by the painter Gianbecchina, stuccoes and paintings of different periods.