Barcelona is a city located in the northeast of Spain. It is the capital of the autonomous region of Catalonia and the second most populous city in Spain, with a population of 1.6 million in the city proper and about 5.5 million in the metropolitan area. Barcelona is the 12th most populous city in the European Union. The origins of Barcelona date back to the Roman period, when it was known as Barcino. In the Middle Ages, it was a prosperous merchant city and a major cultural center. In 1992, Barcelona hosted the Summer Olympics.

The city of Bacau is located in the northeast of Romania, in the historical region of Moldavia. The first mention of the city dates back to the year 1408, when it was mentioned as a village called "Vaslui de Sus". The city was later developed by the Moldavian prince Stephen the Great, who built a fortress there in 1466. The city became an important commercial and cultural center in Moldavia. In the late 19th century, Bacau was annexed by Romania and became the capital of the Bacau County. The city suffered heavy damage during World War II, but was rebuilt afterwards. Bacau is now a major industrial center and transportation hub in Romania.