We continue our special series "Beyond the Wall", seeking breakthroughs in thinking that are transforming China and leading its future. Today, we focus on city designs. By 2050, nearly 10 billion people will share the planet, as mega-cities rise and technology reshapes the urban landscapes. How can the rising population be accommodated? And how can future buildings keep certain cultural values? CGTN correspondent Han Bin interviews two leading Chinese architects, who share their visions in designs for the future.

WANG SHU, FOUNDER FIRM AMATEUR ARCHITECTURE STUDIO "The richness and diversity of all the cultures we can see are being accumulated in time. When we enter such an era of rapid construction, how to create richness and diversity requires a completely different mindset."

MA YANSONG, FOUNDER MAD ARCHITECTS "I don't want to copy the tradition, I want to create something totally new. But you can borrow or inspired by traditional values."

WANG SHU, FOUNDER FIRM AMATEUR ARCHITECTURE STUDIO "The basic source of my creation is not simply Chinese tradition. My basic source is not a simple Chinese background, but how to get to know our own culture. Much of what I am concerned about is the value of traditional Chinese culture in dealing with problems in today's cities. It is exactly China's own tradition that offers a lot of possibilities for resolving those problems."

MA YANSONG, FOUNDER MAD ARCHITECTS "But we have to face contemporary challenges. We have to build high-rise, we have to have density in the modern city. The problem today in my eyes, was everyone living in the city but everyone at the same time, they have to compromise."

WANG SHU, FOUNDER FIRM AMATEUR ARCHITECTURE STUDIO "There are moral principles behind the choice of materials. When I chose old materials and collected old bricks, I wanted to directly face a real problem, that is, I saw a lot of traditional buildings being demolished. As a contemporary architect, you must face these questions and answer them."

MA YANSONG, FOUNDER MAD ARCHITECTS "Modernization means you often build the big buildings to show off the technology, the power, and you use a lot of new materials. I think architecture should be soft, architecture should be natural, architecture can be landscape itself."

WANG SHU, FOUNDER FIRM AMATEUR ARCHITECTURE STUDIO "Reinforced concrete is actually a quick and inexpensive material. The problem I encountered was that natural building materials, including the way it works, are basically incompatible with modern technology. In this case, how can you make modern technology, which you have to use, coexist and be compatible with natural materials?"

MA YANSONG, FOUNDER MAD ARCHITECTS "I think challenging the tradition was also part of the tradition to create new things. I think the new building has to shape the new world, new need and function, but the spiritual philosophy inside architecture can be continue from the past."

HAN BIN BEIJING "Half of the world's population now live in urban areas. Modern construction has in some way re-shaping the way we live. How to make our future cities more sustainable, and eco-friendly, is a challenge that goes far beyond the four walls."

WANG SHU, FOUNDER FIRM AMATEUR ARCHITECTURE STUDIO "I think a big problem with China's urbanization is that it is too fast. The massive destruction of traditional parts has led to the disruption of urban culture, including the continuity of life. When you have a lot of damage, where is the source of innovation?"

MA YANSONG, FOUNDER MAD ARCHITECTS "The architecture and urbanism should be more about the relationship between human and nature. That was missing in the modern cities."

WANG SHU, FOUNDER FIRM AMATEUR ARCHITECTURE STUDIO "I think the future direction of Chinese cities must not be reflected in more and more iconic buildings. It should reflect a more ecological, multi-layered, high-density city."

MA YANSONG, FOUNDER MAD ARCHITECTS "I often want to do something very different from the modern architecture. The concept, I would say, it's inspired from the idea how to combine nature and architecture."

WANG SHU, FOUNDER FIRM AMATEUR ARCHITECTURE STUDIO "Architecture is to create a space for sheltering from the wind and rain. The city is the same, though on a larger scale. It has to accommodate a certain kind of life. This kind of life has a certain way of living. Such living holds certain values."

MA YANSONG, FOUNDER MAD ARCHITECTS "I think architecture is purely spiritual activity, how people understand the environment around them."

WANG SHU, FOUNDER FIRM AMATEUR ARCHITECTURE STUDIO "The biggest conflict is between nature and human society. The core issue of future cities is this question: How do we survive with better ecological quality?"

MA YANSONG, FOUNDER MAD ARCHITECTS "I think the future architecture should provide ideal environment, spiritual environment. So, architecture has to have imagination, has to have a spiritual meaning."