Revitalization of Prague’s Riverfront / petrjanda/brainwork
Urban context. Prague’s riverfront area is a public space of city-wide significance, enabling a unique symbiosis of public space with the spinal cord of the city: the Vltava River. In the regulated part of the banks, the riverfront architecture becomes the backbone for the river spinal cord, which, through the individual “vertebrae” of the embankments, holds the skeletal system of the city on which the entire urban structure forming its body is hung. This skeleton should not be stiff, mounted and petrified as a monumental relic, but should allow the flowing and cultural life of all-Prague significance based on architectural and content authenticity. In our revitalization, we initiate this layer and create a functional tension between the opening of the vaults and their content based on unique contact with the exterior, the tension between the “splendid isolation” of the immediate relationship with the river and the secondary connection to the city from the upper level of the embankment. We work with a characteristic approach to spatial detail; our interventions contrast, and at the same time, complement the whole with meaningful (sensory) fragments with the same principle as the eye complements the face; it is its sensor, as well as an integral part.
The vast revitalized riverfront area stretches along the three Prague embankments: Rašín, Hořejší, and Dvořák, almost 4 km in length. The completed first phase is Prague’s largest investment in public space after the revolution in 1989, the first of this kind, and with great sociocultural impact. It focused on the reconstruction of 20 vaults in the riverside wall (originally ice storage areas). Instead of creating classic interiors, the vaults are merged with the exterior with maximum contact with the riverfront area and the river.
Program. The vaults will serve as cafes, clubs, studios, workshops, galleries, a library branch, space for neighbour meetings, and public toilets. The architectural design works with modular diversity, the spaces are designed as a detailed base that includes all operational and technical facilities and a bar that can be moved to different positions. There is a user’s manual that contains the identification of the individual tenants and the addition of built-in elements (the insertion of floors into large vaults, exterior bar, etc.) Emphasis is placed on the possible adjustment of each of the vaults so that they gain consistent integrity through the equipment of each tenant with their seating furniture and interior elements. As architects, we supervise the individual adjustments so that the basic vision of the area is preserved while achieving authenticity for each tenant. We try to be support for the tenants and stay in the background architecturally, allowing a diversity of opinions. Although this often means different architectural sensitivity, we believe this will complement our basic vault design through another layer. Most of the tenants who co-created the phenomenon of the riverfront area will continue there and new projects have been selected from a whole spectrum of plans in an open public competition. We believe they will socially complement the riverfront area and offer various content and program concepts that will cater to all needs.
As part of the architectural revitalization, we initiated the creation of a methodology for the riverfront area program. The position of curator was created to complement the functional triangle of manager–architect–curator, with an authority overseeing the cultural and social quality of this valuable public space.
Architectural design. The interventions symbiotically merge with the original architecture of the riverside wall, into which they naturally fuse; by using the acupuncture strategy, they re-create a monumental whole. The aim is the most direct connection with the riverfront area with the maximum opening of the spaces inside the wall. The architectural design responds to the context of the place and works with minimal artistic means that allow purging of the existing shapes and relations and finding new interconnection views and possibilities arising from the environment of the embankment.
The six vaults on the Rašín Embankment are built following the almost circular arc of the upper part of the existing openings. The design itself is based on a tiny intervention, which takes more than it adds and brings the existing quality back in a contemporary way, creating a unique situation and opportunity. The former stretch metal curtain wall and stone constructions built into the original bridge arches of the riverfront wall were knocked down and replaced with large-format glazed round windows that open by diagonal rotation inside the frame. The entrance portals are designed as atypical steel frames with dilated elliptic glass weighing 1–1.5t. The stone arched linings of the existing portals are completed with stone stepped volumes following the former steps allusion, which hide the installation shaft, air-conditioning vent, and anti-flood control elements.
The elliptical pivoting windows made of organic glass 7cm thick and 5.5m in diameter weigh approximately 2.5t. Each has a unique shape and, due to their size exceeding the standard glazing, these are probably the largest pivot windows in the world. Opening and closing are engine powered. For the operation of the inner spaces, the windows are fixed in the position of 60% of its opening. Other options are automatic opening with motion-detecting sensors, or they can be opened by the bar staff. The fourteen vaults on the Hořejší Embankment have steel sculptural entrances carved into the jamb in such a way that they connect the vault with the riverfront area in the entire space when opened. In the vaults with public toilets, the entrance wings follow a smooth arc into the interior membrane separating the cabins from the public area.