Interior Architecture and the Spiral Tower

Interior Architecture and the Spiral Tower

The Mukaab’s most extraordinary architectural element is invisible from the outside. Within the 400-meter cube’s solid exterior walls rises a spiral tower — described by the New Murabba Development Company as “a tower atop a spiral base” — that constitutes the world’s first fully enclosed skyscraper. This internal structure, surrounded by the 300-meter holographic dome and wrapped in digital projection surfaces, creates a spatial experience that has no precedent in architectural history.

The Skyscraper Within a Skyscraper

The concept of enclosing a full skyscraper within a larger structure challenges fundamental assumptions about how tall buildings interact with their environment. Conventional skyscrapers are defined by their relationship to the sky — their height creates views, their facades mediate between interior and exterior conditions, their crowns mark the skyline. The Mukaab’s internal tower exists in a controlled interior environment where the sky is replaced by holographic projections and the exterior conditions are managed by the cube’s facade system rather than the tower’s own envelope.

This arrangement creates architectural freedoms impossible in conventional construction. The internal tower does not need to resist wind loads, because the cube’s mega-frame shields it from external forces. It does not need to manage rain, because the cube’s roof system provides complete weather protection. Its facade can prioritize visual permeability and spatial connection over weather-tightness, creating open relationships between the tower and the vast atrium spaces surrounding it.

The spiral base that supports the tower adds a kinetic quality to the interior experience. Visitors ascending the spiral encounter continuously shifting perspectives of the interior volume, the holographic dome above, and the activity at different levels of the cube. The spiral form also provides a continuous ramp-like circulation path that complements the vertical transportation systems with a more gradual, experiential mode of ascent.

Observation Decks and Rooftop Garden

The spiral tower includes observation decks at multiple levels, offering views not outward over Riyadh — those are provided by the cube’s exterior walls — but inward across the Mukaab’s interior volume. These observation points allow visitors to comprehend the scale of the enclosed space, which at 64 million cubic meters defies intuitive spatial understanding.

A rooftop garden crowns the spiral tower, creating an elevated green space within the cube’s protected interior. This garden, suspended hundreds of meters above the ground floor yet entirely enclosed by the cube’s structure, represents a novel typology — an aerial park that exists independent of weather, wind, and ultraviolet exposure. The garden’s microclimate is managed by the building’s AI climate control systems, maintaining conditions suitable for vegetation regardless of the extreme desert conditions outside.

Mixed-Use Interior Organization

The Mukaab’s 2 million square meters of floor space houses an extraordinarily diverse program. Residential units, hotel rooms, retail spaces, restaurants, cultural venues, entertainment facilities, office space, and community infrastructure must coexist within a single structural envelope. The interior architectural challenge is to organize these uses so that each functions optimally while contributing to a coherent spatial experience.

The organizational strategy appears to layer uses vertically, with public-facing retail, entertainment, and cultural spaces concentrated at lower levels to maximize accessibility and foot traffic, hospitality and commercial spaces occupying middle zones, and residential units positioned at upper levels where privacy and quiet can be maintained despite the building’s public nature.

The structural design accommodates this mixed-use program through transfer structures that allow column-free spans in retail and entertainment zones while providing the regular structural grid required for residential and hotel floor plates. The challenge of acoustic separation between nightlife entertainment venues and residential sleeping areas within the same structure requires sophisticated building physics solutions that go beyond conventional mixed-use design.

The Holographic Experience

The interior architecture is inseparable from the holographic dome technology that transforms the cube’s interior volume. The 300-meter holographic structure creates a digital sky above the spiral tower and surrounding spaces, capable of projecting environments ranging from realistic nature scenes to abstract digital art to simulated extraterrestrial landscapes.

This technology transforms the interior architecture from a fixed physical environment into a programmable space where the perceived environment changes on demand. A visitor might experience the tower rising through a projected forest canopy in the morning and a Martian landscape in the evening. The architectural experience becomes temporal and variable rather than permanent and fixed.

The integration of holographic technology with physical architecture requires careful coordination between the structural systems that support projection surfaces, the lighting design that prevents interference with holographic displays, and the spatial planning that ensures sightlines to projected content from key vantage points within the spiral tower and surrounding spaces.

Structural Requirements of the Interior Tower

While the spiral tower benefits from protection against external wind and weather, it faces its own set of structural demands. The tower must support its own considerable weight — residential floors, restaurants, observation decks, and the rooftop garden — through a structural system that operates independently of the cube’s mega-frame yet coordinates with it to prevent differential movement.

The tower’s spiral geometry creates non-standard structural loads. Unlike a conventional tower with symmetric floor plates, the spiral form generates torsional forces as loads are transferred along the helical path of the structure. The base of the spiral must resolve these torsional forces into the foundation system, adding complexity to the already demanding pile design below the Mukaab.

Connection points between the spiral tower and the cube’s mega-frame serve dual purposes: they provide lateral bracing for the internal tower and support the holographic dome projection surfaces that span between the two structures. These connections must accommodate differential thermal expansion, structural settlement, and dynamic movements from the vertical transportation systems while maintaining precise alignment of the projection surfaces.

The Atrium Experience

The spaces between the spiral tower and the cube’s inner walls constitute some of the largest enclosed atrium volumes in architectural history. These void spaces — measuring hundreds of meters in height and tens of meters in horizontal extent — create a sense of scale that challenges human spatial perception. Standing at the base of the Mukaab and looking upward past the spiral tower to the holographic dome 300 meters above creates a visual experience that has no equivalent in any existing building.

The atrium spaces serve practical functions beyond visual drama. They provide circulation space for the building’s users, daylight distribution from the facade’s glazed elements to deeper interior zones, and the air volume necessary for the climate control systems to manage thermal stratification across the building’s height. The atriums also create the spatial context for the holographic projections, providing the depth and volume needed for three-dimensional holographic imagery to achieve its intended visual impact.

Balconies, sky bridges, and viewing platforms at various levels along the atrium walls connect different zones of the building while offering constantly changing perspectives of the interior volume. These transitional spaces between the spiral tower and the cube perimeter create opportunities for informal social interaction, wayfinding orientation, and the simple pleasure of observing the building’s activity from elevated vantage points.

Programming the Interior Experience

The Mukaab’s interior architecture is designed to be programmed and reprogrammed over time, adapting to changing cultural preferences, technological capabilities, and market demands. The holographic dome’s projection capabilities allow the interior environment to be transformed for special events, seasonal celebrations, and cultural programming without physical alteration to the architecture.

This programmability extends to the building’s retail and entertainment zones. Floor plates designed with maximum flexibility — long column-free spans, raised floor systems for services redistribution, and modular partition systems — allow commercial tenants to reconfigure their spaces as business needs evolve. The building’s IoT monitoring systems track usage patterns across different zones, providing data that informs decisions about programming changes, spatial reconfigurations, and services adjustments.

The interior architecture must also accommodate the estimated 90 million annual visitations to the New Murabba development, a significant portion of which will flow through the Mukaab itself. At peak periods, the building may host tens of thousands of visitors simultaneously, requiring crowd management strategies embedded in the architectural design — wide circulation corridors, multiple vertical transportation options, clear sightlines for orientation, and distributed service points that prevent bottleneck formation.

Precedents and Influences

While no existing building provides a direct precedent for the Mukaab’s interior architecture, several projects offer partial comparisons. The Marina Bay Sands in Singapore combines hotel, retail, entertainment, and cultural uses within a dramatic structural form, though at a fraction of the Mukaab’s scale. The Dubai Mall integrates retail with aquariums, ice rinks, and entertainment venues in a single complex. Theme parks like those operated by Disney and Universal create immersive environments using technology and architectural scenography.

The Mukaab’s interior architecture synthesizes elements from all these precedents while adding dimensions none of them possess. The spiral tower introduces genuine vertical urbanism rather than the horizontal sprawl of theme parks and malls. The holographic dome creates immersive environments at a scale that dwarfs any existing theme park attraction. The residential and hospitality components add a permanence and intimacy that purely commercial or entertainment destinations lack.

The closest conceptual precedent may be the proposed Shimizu Mega-City Pyramid in Tokyo — a 2,004-meter-tall pyramid proposed in 2004 to house 750,000 people — which similarly envisioned a self-contained vertical city within a geometric enclosure. That project was never built, leaving the Mukaab as the most advanced attempt to realize the vertical city concept within a single geometric form.

Engineering Integration and Services Distribution

The interior architecture of the Mukaab cannot be understood in isolation from the engineering systems that make it habitable. The spiral tower, the atrium volumes, and the holographic dome all depend on mechanical, electrical, and plumbing systems of unprecedented scale and complexity. The climate control infrastructure must manage 64 million cubic meters of enclosed air, maintaining comfortable conditions across zones ranging from the rooftop garden atop the spiral tower to the retail concourses at ground level. The thermal stratification inherent in a 400-meter-tall enclosed volume — where warm air rises naturally to the top — requires active management through displacement ventilation, stratification barriers, and zone-specific temperature control.

The spiral tower’s helical geometry creates particular challenges for vertical services distribution. Conventional buildings distribute mechanical risers, electrical bus ducts, and plumbing stacks vertically through straight shafts aligned from floor to floor. The spiral tower’s continuously rotating floor plates mean that riser locations shift horizontally as they ascend, requiring flexible routing systems that follow the helical path without creating maintenance-access complications. This routing challenge affects every building service — from chilled water pipes serving the climate control system to fiber-optic cables serving the IoT sensor network — and multiplies the coordination effort between the interior architect and the engineering design team at AtkinsRealis.

Vision 2030 and the Experience Economy

The spiral tower and its surrounding interior environment are designed to serve Saudi Arabia’s Vision 2030 objective of establishing the Kingdom as a global tourism and entertainment destination. The interior architecture’s immersive quality — combining physical architecture with holographic projection, programmed environments, and experiential retail — positions the Mukaab as a participant in the global experience economy, where consumers increasingly value memorable experiences over material goods.

This strategic alignment with Vision 2030 influences every aspect of the interior architecture. The spiral tower’s observation decks, the holographic dome’s projection capabilities, and the atrium’s dramatic spatial volumes are all designed to create social-media-worthy moments that drive organic marketing and repeat visitation. The projection of 90 million annual visits to New Murabba depends on the interior architecture delivering experiences that justify international travel — a high bar that requires the interior design to exceed the standards set by existing destinations including Dubai’s Burj Khalifa observation deck, Singapore’s Marina Bay Sands SkyPark, and the immersive environments of major theme parks worldwide.

Future Adaptability

The interior architecture’s success will ultimately be measured not by its appearance at opening but by its ability to remain relevant and functional over decades. The technology systems that create the immersive experience will evolve rapidly, requiring interior infrastructure that can accommodate technological upgrades without major architectural disruption. The cultural programming will change with shifting audience preferences. The commercial mix will adapt to market conditions that are impossible to predict decades in advance.

Designing for this adaptability requires a clear distinction between the building’s permanent architectural infrastructure — structure, major circulation, primary services distribution — and its adaptable programmatic elements — interior partitions, retail fit-outs, technology installations, and entertainment attractions. The spiral tower and holographic dome belong to the permanent infrastructure, defining the building’s spatial character for its entire lifespan. The uses that inhabit the spaces between and around these elements must be free to evolve without constraint from overly specific architectural decisions made during initial design.

For related coverage, see facade engineering, smart building systems, construction progress, and floor area analysis.