The city forms the fundamental structure that allows the development of the natural habitat of the human being. From the domain of agriculture, the early appearance of urban centers in the history of humanity can confirm this phenomenon. As Romano Guardini points out, starting from the examples of Mesopotamia and Egypt to the cities of the Enlightenment, the construction of the city maintains an organic balance with nature that is related to the technical limitations of the moment and the effect of time. Since the Industrial Revolution of the nineteenth century and with the appearance of the "machine age", as Le Corbusier would say, the speed of the growth of cities has increased exponentially. Thus, and according to the UN, currently 55% of the world's population lives in cities. But the future forecast draws an upward curve for 2050 rising that percentage up to the 70% of the population; in the next 30 years it is estimated that around 6.600 million people will live in cities, which means that their evolution and development will continue to be frenetic both quantitatively and qualitatively. New types of housing, functions and infrastructures, together with the growing ecological sensitivity and the digitalization of design and construction processes, will turn the city into one of the phenomena of greater economic and cultural intensity in the coming years.

On the other hand, its cultural dimension, less rational and quantifiable – "more irrational and subconscious", according to Guardini – has undergone a similar process. Citizen awareness of the imaginary of the city, its character and identity has developed a recognition of what has been built, of the city. In just a century and a half, since the mid-nineteenth century and with the appearance of the printed image and photomechanics, this recognition has resulted in the gradual appearance of institutions and jurisdiction that have promoted the identification, cataloguing and subsequent protection of this heritage.

In addition, the speed of the real estate and construction processes and their impact on the vertiginous transformation of the city have led to a zeal on the general building heritage that has resulted in different citizen demonstrations of concern about the development of the city. Thus, the urban is no longer an exclusive matter of reflection of the academy but increasingly interests all citizens.

We are therefore in front off a scenario in which the development of the city is shown as a diatribe between what is already built and the buildable, about what was and what will be.

On the one hand, the phenomenon of the city is inherently linked to the transformation of the environment –or the destruction and creation of the environment–. The process is similar to the cells of a living organism: to guarantee life, they must die and give way to the creation of new ones. If this cell death and reproduction does not occur, they become cancerous.

On the other hand, the city is the history of a multitude of architectural and urban events that transcend their own material nature, leading to a collective cultural construction. If we aspire to a constant and infinite enrichment of this culture, the construction of this immaterial requires the identification and care of those goods worthy of this value.

Polarization towards one extreme or the other can provoke caricatures of the city that we aspire to create. As Antonio Miranda would call one of his books, "neither robot nor jester": the danger of a blind attitude in an infinite developmentalism is ridiculous and similar to the idea of the aspiration of a city frozen in time.

This is the challenge that arises in the (re)construction of the future city: to combine the natural development of transformation processes –which are increasingly efficient and fast– with the most appropriate material and immaterial values.
Thus, the third edition of the Mugak/ Biennial, under the headline 'Heritage and Modernity', aims to be the background scenario that brings together all the agents involved in the construction of the city: technicians, citizens, economic agents, administration, academia, industry, etc. The goal is none other than to enrich the discourse with the purpose of underlining integrating criteria and drawing the best of the aspirations for our cities.

The Mugak/ programme for 2021 will be based on three pillars: the citizen, the academic and the technician. Thus, for example, different citizen and business groups will focus on various manifestations of architecture and design that will allow us to identify this immaterial asset of the city. On the other hand, the academy, the School of Architecture of the Basque Country, will invite us to reflect on urban typological phenomena, students' views on the city and the identification of fundamental trajectories in its construction. Finally, the incorporation of technicians and professionals from the city will allow us to understand from the concrete point of view exemplary actions in order to enrich the debate.

All these activities and manifestations will be developed in the heart of our cities with the intention to invite its inhabitants to catalyze all these aspirations in ideas, projects and solutions, in order to create the best of cities.