I'm not sure I saw Évora at its best, since I visited on a cool, rainy autumn day in 2012, but I was impressed with the Roman monuments and Portuguese architecture I saw throughout the city. I joined a walking tour of the city, which started out in the subdued, empty Praça do Giraldo (probably rather deserted as a result of the poor weather), where we had great, uninterrupted views of the Church of St. Anton and a Renaissance fountain. From the square, we walked through back streets filled with the distinctive Portuguese white and yellow-painted buildings that apparently can also be found in colonial architecture in Brazil. In another city square we stopped at the impressive Roman Temple of Évora, which may have been dedicated to Jupiter, rather than Diana; it is one of the most complete monuments remaining from the city's days as a Roman settlement. The tour also visited a section of the old Roman wall around Évora, as well as Roman baths found beneath the city's Town Hall. I enjoyed learning about the city's extensive history, although I think I will need to revisit Évora during better weather in order to fully appreciate the city.
Logistics: Évora is an easy day trip from Lisbon, and can be reached by train, bus, or automobile. The historic center of the city is very walkable.