Derek A. R. Moore oversees the firm’s Airports and Transportation practice and has played a leading role in the planning and design of large projects for airport and rail terminals around the world. Moore holds advanced degrees in the history of art and architecture, and has lectured and published in a number of fields. He is a fellow of the American Academy in Rome and has taught history and theory of architecture at Columbia University.
The COVID-19 pandemic has upended all of life’s rituals and routines — great and small, sacred and secular. So, the news in late June that the Hajj — the annual Muslim pilgrimage to Mecca and Medina that is one of the “five pillars” of the faith, and considered an obligation for those physically and financially capable to make once in their lifetime—would be canceled came as a surprise to probably no one, although it certainly disappointed millions of Muslims and others around the world.
Since 1981, the world’s gateway to the holy cities has been the Hajj Terminal at Abdul Aziz International Airport in Jeddah. Imagining that vast, largely open-air terminal during pandemic conditions has actually revealed the significant public health advantages of its design. In fact, this only adds to a list of innovations — in operations, flexible planning, structural engineering, mechanical engineering and ventilation, not to mention cultural resonance — which took their first monumental form in the Hajj Terminal. Due perhaps to its unique use — mainly during a single, intensive six-week period each year — and its very open-air format, the Hajj Terminal has gone largely unrecognized as the seminal airport terminal of our time. It’s high time for a reassessment of this remarkable project.
First, a clarification of the current state of affairs. After initial reports of an outright cancellation, the Saudi Ministry of Hajj and Umrah announced that this year’s Hajj, taking place between July 28 and August 2, would be limited to some 1,000 pilgrims already residing in the Kingdom (compared with the nearly 2.5 million travelers accommodated in 2019). These fortunate few, not limited to citizens of Saudi Arabia, will represent many nationalities, but they must be younger than 65 years of age and have no chronic health conditions. Furthermore, they are required to be tested for COVID-19 upon arrival; they must wear masks and maintain a minimum of 1.5 meters’ distance from other pilgrims during the multiple rituals of the pilgrimage, including the circumambulation of the Kaaba, the most sacred site in Islam.
I wondered, had a severe restriction of the Hajj ever happened before for reasons other than war? This is the year 1441 in the Islamic calendar; the Hajj has been canceled or scaled back only a handful of times since it was first refashioned by Muhammad from a number of pre-existing polytheistic rituals and then codified in the years following his death in 632 CE.
Health and sanitation must have been matters of concern from the earliest days, but the first epidemics spread to and by the Hajj started to occur only in the 19th century, the first in 1831. Pilgrims infected with cholera arrived in Mecca from points east and transmitted the disease to other pilgrims, who then returned to their homelands. Major outbreaks in 1865 and 1893 killed tens of thousands of pilgrims — between 15 and 30 percent of attendance in those years. International conferences in Paris (1851) and Venice (1892) attempted to establish health norms and to prevent the spread to Europe through Egypt by establishing quarantine camps. With the foundation of the Kingdom of Saudi Arabia in 1932, the responsibility for the health and safety of the pilgrims passed officially to the Saudis.
Before air travel, the journey to Mecca was arduous, expensive, and time-consuming. Caravans marshaling at Cairo, Damascus, and Baghdad could take up to 35 days to reach Mecca. Under sail, the voyage from the Muslim communities of Southeast Asia to the port of Jeddah on the Red Sea could take as long or longer, and probably entail more hazards. These immemorial means of travel were briefly supplemented in the 19th and early 20th century by steamship (astonishingly, a British monopoly for the most part) and the Hejaz Railway, built by the Ottomans from Damascus to Medina. Opened in 1908, the railway was closed in 1920 at the fall of the Ottoman Empire — and as a result of having been attacked repeatedly by the forces led by T. E. Lawrence, “Lawrence of Arabia,” and the Arabs during the war.
Many factors converged in the decision by the Saudi government in the 1970s to construct a modern airport terminal at King Abdul Aziz International Airport in Jeddah — their responsibility as custodians of the holy cities, oil wealth, prestige. Even the ascendance of the high-capacity Boeing 747 probably played a role, bringing pilgrims in numbers and at speeds unimagined in earlier epochs.
The Saudis entrusted the design of the terminal to SOM in 1975. At the time, working at distance was slow and cumbersome. SOM committed senior staff to a project office in Jeddah that was more like a camp. Due to the unique use of the facility, the SOM team began from first principles to inform the design: the forecasted number of passengers, the processing and logistics, and the means of transport—aircraft and ground transport by bus to and from Mecca. Deployed across three locations — New York, Chicago, and Jeddah — the multidisciplinary team developed multiple schemes.
The turning point in the design was the realization that a terminal large enough to accommodate the anticipated number of pilgrims arriving and departing within a six-week period — which could fall at any time of year, due to the lunar calendar that determines the date of the Hajj — could not feasibly be air-conditioned in a cost-effective way (despite all the oil-generated power imaginable).
The decision to create an open-air terminal — to enclose only the essential control and gate functions of the terminal, and to shelter the pre- and post-flight waiting, staging, and ground transport areas under cover but unenclosed — triggered a series of notable innovations.
The stars had aligned at SOM to bring together not only a group of driven planners, managers and designers — Gordon Wildermuth, John Winkler, Raúl de Armas, Roy Allen, and others — but SOM’s senior design partner Gordon Bunshaft and one of the great structural engineers of the time, Fazlur Khan. The alchemy of design is ultimately unknowable, and there are few now who were “at the table” when the concept of the great fabric conical tents stretched between masts emerged and was progressively refined. Khan and SOM’s structural engineers applied early computer-aided design and eventually collaborated closely with Owens-Corning, the maker of the innovative Teflon-infused fiberglass fabric that had never before been used on this scale. The sheer size of the terminal is astonishing, even by today’s standards. It covers some 112 acres, or about 45 hectares.
The lineaments of contemporary terminal design are commonly thought to have come together during the 1990s, but several of these key components were formulated in the Hajj Terminal, which opened in 1981. Among these are: the two-way, square grid cellular structural-spatial field supporting a long-span roof; ventilation assisted by “air towers” served from below the primary occupied level; clear sight lines from the curbs to processing functions and out the sides of the building; the balance of a single shared space with semi-private, semi-enclosed enclaves for groups; and a sophisticated response to climate and environment.
Insofar as the Hajj Terminal is a “building,” it consists entirely of structural-spatial modules, set out on a square grid of 45 meters. These structural units are also 45 meters high, which happens to be the maximum allowable height limit for airport buildings other than air traffic control towers. From the ground level, the terminal consists of a regular field of subtly tapering steel columns supporting the four sides of the conical tents. The columns are doubled along the sides, with sets of four at the corners. But the essential idea — which is so commonplace today — is that a regular field of columns allows for great flexibility in arranging different functions below. These functions can, within reason, be treated as “furniture” to be rearranged when needs change. Indeed, since its opening, there have been a number of such modifications within the regular grid of columns — the introduction of a small hotel, more enclosed eateries, and the like. The current government is embarking on a more comprehensive program to update the amenities for today’s pilgrims. The basic spatial-structural framework of the terminal will allow that while retaining its essential qualities.
To mitigate the intense heat and humidity of the Red Sea region, the designers created openings at the peak of the conical tent forms to draw the hotter air up and out of the terminal space. The simple movement of air creates a more comfortable environment for pilgrims at ground level, while the fabric roof blocks glare and some 76 percent of solar radiation without absorbing and re-radiating that heat at night.
From the 1990s on, such air towers have become commonplace in contemporary airport terminal design as a means of delivering conditioned air from below within high-ceiling spaces. The Hajj Terminal is the first large-scale use of this technique.
When pilgrims arrive at the Hajj Terminal and pass through immigration and customs, they might spend a dozen hours waiting for organized transport to Mecca or Medina. Most of the terminal’s surface area consists of these waiting areas. The open area is divided into five large modules measuring 135 by 300 meters. These modules provide a clear path from customs to curb and back to check-in upon departure. Each module is provided with essential services and discrete group waiting areas, some with cooking facilities. This arrangement allowed for a sense of national identity within the global community of the faithful gathering for the Hajj.
Setting aside the religious dimension, contemporary airport terminal design attempts to break down the immense scale of the building into areas that are more comprehensible and inviting, without losing the sense of general orientation and wayfinding that is also necessary to navigate such spaces. This “passenger experience” dimension of the Hajj Terminal design is not fully appreciated.
Many designers today are planning outdoor areas for new terminals. The ultimate source of this idea is standing in Jeddah.
This ingenious, large-scale, and unprecedented solution could not be replicated in an enclosed terminal, but it informed the principle of displacement ventilation and was assisted by the introduction of “air towers” at the ground level. Viewing early photographs of the Hajj Terminal in use, one’s eye goes to either the pilgrims in their distinctive national garb or to the billowing tent structures overhead. However, look closely and you will see a series of octagonal pylons with rows of nozzles around them. These “air towers” deliver fresh air at the occupied level to assist the stack effect of the tents and provide additional temperature mitigation for the pilgrims.
Born of necessity, it turns out that the open-air format of the Hajj Terminal provides healthier conditions during the current pandemic, allowing the sunlight, natural humidity, and air movement to create a safer environment than a densely packed interior space. Many designers today are planning outdoor areas for new terminals, and a few small terminals that are mainly open air in benign climates have received renewed attention. The ultimate source of this idea is standing in Jeddah.
These design moves are closely bound up with the form, function, and technology of the superstructure, but are transferrable to more conventional systems for fully enclosed and conditioned terminals. And that is what happened. Most of these strategies are taken for granted today, but were unknown or uncommon when the Hajj Terminal was designed. The utterly unique and singular purpose of the terminal for the pilgrimage has meant that the Hajj Terminal’s influence has gone largely unacknowledged. The terminal became known only for the tents, while its other innovations were obscured by a superficial understanding of what lies beneath them.
Finally, the matter of the tents — the salient visual feature of the Hajj Terminal. Along with the tapering steel columns and cable system, they form perhaps the most perfect synthesis of visionary architecture, advanced structural engineering, technical mastery of new materials — all in a form that is deeply resonant of the place and representative of its function. There have been superficial imitations in terminals large and small, but no subsequent use of a fabric roof structure that so elegantly plays many roles. In addition to forming a relatively lightweight covering for a vast area, and performing a key role in mitigating the high ambient temperatures of Jeddah’s climate — almost no matter the season in which the Hajj falls — the conical form of the Hajj Terminal cells allude in the subtlest way to the canvas tents erected by and for the pilgrims in vast camps around Mecca and Medina since the earliest centuries of the Hajj. Some 45,000 tents are still erected to house pilgrims not staying in the increasing number of hotels and hostelries.
In my view, it is critical to an appreciation of the achievement of the Hajj Terminal to know that the designers first envisioned a fully enclosed and mechanically cooled terminal. They did not start with a superficial mimicking of the pilgrim tents. Numerous post-war architects had dreamed of realizing in permanent form the concepts of lightweight exhibition structures of the 1920s and 1930s, such as those designed by Le Corbusier. Even considering the large tensile structures for sports venues of the 1960s and 70s designed by Frei Otto, the technical prowess achieved in Jeddah of scaling up multiple innovations to colossal size in relatively new materials and systems is impressive.
In the end, the structural rationale of the terminal, growing from the functionality and flexibility of the square grid, and rising through the anticlastic stretching of the high-tech fabric, arrived at an allusion to the pilgrim tents. The reference could not have been lost on the waves of pilgrims. The aptness could not be more profound. The synthesis of architecture, function, structure, environment and culture no more complete. These remain central aspirations for terminal designers today. There may be no building more seminal to its type than the Hajj Terminal, yet largely unknown today. The result was both deeply resonant and entirely new.
Several years ago I had the good fortune to be able to make my own secular pilgrimage to the Hajj Terminal. It did not disappoint. The terminal’s immense size makes an instant impression. Although there are no other buildings around it to lend a sense of scale, the terminal seems to hover high above the desert. It is true that the “furniture” — the functional partitions and passenger services at the ground plane — needs upgrading for operational, commercial, and climatic reasons, after decades of use. But the brilliant, truly awe-inspiring framework remains.
The one great surprise for me was to see that the west half — all 230,000 square meters of sheltered area — was never finished with the passenger facilities at the ground level. The superstructure of tents looms over the rough ground — not like a ruin that has been diminished by time, but a luminous shelter waiting to be inhabited by the next generation of pilgrims. Would this not be an ideal canvas on which to design a model pandemic-resistant terminal for this new age? As they say in Arabic, “inshallah.”
This article originally appeared on Medium.