From the World Heritage inscription:
The examples of architectural and urban design in Úbeda and Baeza were instrumental in introducing to Spain of Italian Renaissance design criteria, but had their origins in the Islamic period. The exceptional feature of this cities lies on the fact that they have structured in a dual complementary and inseparable fashion. This duality makes them operate in many aspects as a single city, with their own affinities and features and differential shades of meaning characterizing their morphology and historical development until present times. The central areas of Úbeda and Baeza constitute outstanding early examples of Renaissance civic architecture and urban planning in Spain in the early 16th century, and achieved exceptional development characterized by the influence of humanism. This development of constructive solutions in the field of stereotypy made it possible to adopt complex architectural solutions, which have had an evidenced and relevant impact on the architecture of Spanish America, confirming, in this versatile way of dialogue with the American cultural world, their character of an open and universal project.
The two small towns, Úbeda and Baeza, some 10 km from each other, are located in southern Spain between the regions of Castile and Andalusia, on the northern slopes of the valley of the Guadalquivir River. Being on the frontier of the two regions, the towns have assumed a character of contrasts, which is reflected in the urban fabric that is of Arabic and Andalusian origin and more northern influences. In the 8th century Moorish conquest the towns became fortresses, which quickly attracted fortified urban settlement with a characteristic layout of narrow irregular streets. Úbeda was conquered by he Christian army of Ferdinand III in 1233-34, playing a role as a frontier fortress after the fall of Granada in 1492. Baeza, a minor settlement in the Roman times, was taken over by the Christians in 1226-27. Both towns prospered for a time in the 16th century, and have survived until the present day. They are an exceptional example of the distribution of urban functions, so that the sum of the monumental site of Baeza (public, ecclesiastic and educational) and of Úbeda (aristocratic and palaces) make up a complete Renaissance urban scheme of high architectural quality.
I drove to the towns of Ubeda and Baeza on my way to Granada. They are very close and if you visit one you can easily visit the other. It can also be easily visited on a day trip from Granada if you are in the area.
That being said, I didn’t think this was one of the most stellar examples of a World Heritage site. Baeza was far more photogenic than Ubeda and it was easier to walk around the city to explore its heritage. Of the Spanish UNESCO sites I’ve visited, I was least impressed with this one. It is definitely on the margins of what I would call “world heritage”. They are nice towns, but I don’t think they quality as world level.
View my complete list of UNESCO World Heritage Sites.