In the center of the new CBD (central business district) development area in northern Guangzhou, Guangzhou Baiyun Station is a high-speed rail TOD (Transit-Oriented Development) and the only one of its kind in the world at the time of design.

Comprising a station of 11 platforms and 24 tracks (connecting the Guangzhou-Zhanjiang High-Speed Railway, the Beijing-Guangzhou High-Speed Railway, the Beijing-Guangzhou Railway, and the Guangzhou-Qingyuan Intercity Railway), six subway lines, and three bus terminals, this enormous transportation hub is expected to have an estimated daily user base of 360,000 people. The development area above the station is approximately 170,000m2, and the surrounding area, including offices, commercial facilities, Serviced Apartments, and housing, has been developed as an integrated whole, covering an area of approximately 500,000m2. It focuses on the efficient use of land in the urban area and the creation of a sustainable transportation system centered on public use while proposing a rich mixed-use of functions and the future of urban public space.

The most significant features of the development are "the Transit Loop" which effectively realizes the concept of the "station connecting divided urban precincts", the Grand Canopy facade that creates a welcoming sense of identity, and the "Station Core", a bright transfer space, connecting the various modes of public transportation.

High-speed rail tracks are generally built above ground to minimize development costs and environmental impact, consequently dividing the city. As a solution, a three-dimensional ring-shaped pedestrian space, "the Transit Loop", was constructed from the metro transfer hall on the second basement floor to above the high-speed rail tracks. Urban functions and public spaces were placed adjacent to it, creating a foundation for the integration of the station and the town.

The Transit Loop has a height difference of five stories from the second basement to the third floor. Starting its journey from the subway hall, it splits into two (north/south direction), following arcs on both sides and connecting to another subway hall approximately 400 meters away. The pedestrian route features a variety of greenery on the east and west sides while combining public spaces such as rest areas. It is a place for relaxation and recreation not only for station visitors but also for local people to spend their time.

Furthermore, a transformative public space, Breathing Square, was placed where the Transit Loop coming from the east-west metro halls intersects vertically with the north-south high-speed railway on the third floor. Usually, this space is used as a plaza for local events. However, during peak seasons, such as the Chinese New Year and National Day, an additional station entrance is opened to accommodate the overwhelming number of travelers, and the plaza functions as the station front. This is one of the symbolic features of TOD, where the station, the surrounding development, and the community transform as if breathing in response to each other's presence.

Viewed from above, the Transit Loop is arranged in a circular pattern with the high-speed rail station building on the inside and three bus terminals and public space, such as a transportation plaza, as well as offices, hotels, and commercial facilities on the outside. This loop is the most important feature of Baiyun Station, serving as a vital link to connect the entire area and region through its rich public spaces.

What does a station mean to the people? Much consideration led us to the Grand Canopy, large 30-meter cantilevered eaves on the station facade. Under the Grand Canopy, inspired by Guangzhou's symbolic cotton flower, is a public space open to the community. Station visitors use it as a plaza, promenade, playground, and running track.

The structure that supports the petals is realized by combining two steel columns that follow the outline of the petals. Without adding any decorative materials to the box steel columns but exposing them as the frame of the petal, the design directly expresses its structural functionality.

The petal structure is supported by the columns of the metro platform on the fourth basement floor. Considering the load restriction, a PTFE membrane was adopted to reduce the weight of the petals, providing the necessary structural lightness and aesthetics. There are few restrictions on the manufacturing dimensions of the membrane material, as it is easy to process and can be rolled up for transportation. The use of 30-meter-long membranes realized a seamless "cotton flower" facade.

During events or at night, up-lighting placed at the base of the petals can project a variety of lights onto the membrane, communicating a changing expression to the city. The spectacle of human activities taking center stage under the giant canvas of the petals contributes to the facade and its symbolism of the station and the city in its new era.

The Station Core is an open atrium that provides vertical circulation between each floor, from the public transportation concourse on the second basement up to the fourth floor above ground. In addition to being a crucial transfer space, it is also the face of the station as the first view for visitors arriving at the facility. The design set out to achieve a "sense of arrival" by creating a pleasant, open, and light-filled space.

The Station Core is a Light Valley filled with natural light at all times, with uninterrupted sightlines. Stretching from north to south, the Station Core captures the sunlight from different directions depending on the time of the day. By analyzing the sun's angle throughout the year, louvers with three different angles were placed along the arched beams to capture the optimal amount of light. Maximum shade was provided where people tend to stay longer, while as much light as possible is introduced into the circulation areas around the escalators on either side.

Fine-pitched collar beams installed between the arch beams act as solar shading louvers, pursuing a unity of architecture and structure where the expression of structure becomes a key design aesthetic. Elegant, symmetrically curved columns are expressed on the inside of the large cantilever of the Grand Canopy station facade that counteract the force acting on the outside and maintain structural stability.

On their journey through the station, people are guided by the light. Although two stories underground, the Light Valley welcomes people by gradually transforming itself from morning to afternoon to evening through different combinations of direct and diffused light throughout the day. The start of station-city integration begins with a comfortable travel experience through natural light.