The Puente Romano (Spanish for Roman Bridge) is a Roman bridge over the Guadiana River at Mérida.
It is the world's longest (in terms of distance) surviving bridge from ancient times, having once featured an estimated overall length of 755 m with 62 spans. Today, there are 60 spans (three of which are buried on the southern bank) on a length of 721 m between the abutments. Including the approaches, the structure totals 790 m. It is still in use, but was pedestrianized in 1991 as road traffic was redirected to use the nearby Lusitania Bridge.
Annexed to the bridge is the Alcazaba of Mérida, a Moorish fortification built in 835. Close to the remains of the Acueducto de los Milagros, there exists another Roman bridge at Mérida, the much smaller Puente de Albarregas.
References:The ancient Argos Theater was built in 320 BC. and is located in Argos, Greece against Larissa Hill. Nearby from this site is Agora, Roman Odeon, and the Baths of Argos. The theater is one of the largest architectural developments in Greece and was renovated in ca 120 AD.
The Hellenistic theater at Argos is cut into the hillside of the Larisa, with 90 steps up a steep incline, forming a narrow rectilinear cavea. Among the largest theaters in Greece, it held about 20,000 spectators and is divided by two landings into three horizontal sections. Staircases further divide the cavea into four cunei, corresponding to the tribes of Argos A high wall was erected to prevent unauthorized access into the theatron and may have helped the acoustics, but it is said the sound quality is still very good today.
Around 120 CE, both theaters were renovated in the Roman style.