Khan al-Umdan ('Caravanserai of the Pillars') is the largest and best preserved caravanserai (roadside inn where travelers could rest and recover from the day's journey) in Israel. Located in the Old City of Acre, it is one of the prominent projects constructed during the rule of Ahmed Jezzar Pasha in Galilee, under the Ottoman era.
Being one of four Khans in Acre, Khan al-Umdan was built in 1784 on the place of the Royal Customs house of the Kingdom of Jerusalem. It incorporates forty columns made of granite that were taken from Caesarea, Atlit and the ruins of Crusader monuments in Acre itself.
Due to its proximity to the port, Khan al-Umdan has throughout its history been an important trading spot. Merchants arriving at Acre used the khan as a warehouse while the second floor functioned as a hostel. Camel caravans once brought produce and grain from Galilean villages to the city's markets and port.
The khan later gained importance to the Baháʼí Faith (as the Khán-i-'Avámid) as it was the site where Baha'ullah used to receive guests, and later the site for a Baháʼí school.
In 1906 a clock tower was added adjacent to the main entrance to the khan to commemorate the silver jubilee of the rule of Ottoman sultan Abd al-Hamid II. It is similar to the Jaffa Clock Tower, a building dedicated to the same purpose, along with five more towers in Ottoman Palestine (in Jerusalem, Haifa, Safed, Nablus, and possibly Nazareth) and over a hundred across the entire empire.
In 2001 Khan al-Umdan, together with the rest of Acre's old city, was designated as a world heritage site. Nowadays, the khan is a major tourist attraction open all hours of the day and used as an open-air stage during festivals in the city, such as the theater festival of Acre during the month of October.
The Roman Theatre of Mérida is a construction promoted by the consul Vipsanius Agrippa in the Roman city of Emerita Augusta, capital of Lusitania (current Mérida). It was constructed in the years 16 to 15 BCE. One of the most famous and visited landmarks in Spain, the Roman Theatre of Mérida is regarded as a Spanish cultural icon and was chosen as one of the 12 Treasures of Spain.
The theatre has undergone several renovations, notably at the end of the 1st century or early 2nd century CE (possibly during the reign of Emperor Trajan), when the current facade of the scaenae frons was erected, and another in the time of Constantine I (between 330 and 340), which introduced new decorative-architectural elements and a walkway around the monument. Following the theatre"s abandonment in Late Antiquity, it was slowly covered with earth, with only the upper tiers of seats (summa cavea) remaining visible.