MIT Sean Collier Memorial

Architecture firm: Höweler + Yoon Architecture

Owner: Massachusetts Institute of Technology

Location: Cambridge, Massachusetts

Category: Development of Design or Design-Thinking (honorable mention)

Situated at the Vassal Street entrance to MIT’s campus, the Collier Memorial honors Officer Sean Collier who was shot and killed on April 18th, 2013, during the manhunt that followed the Boston Marathon Bombing. The memorial marks the site of tragedy with a timeless structure, translating the phrase "Collier Strong" into a space of remembrance with a form that embodies the concept of strength through unity. The memorial is made of thirty-two solid blocks of granite that form a shallow five-way stone vault, holding in the center an aperture, an ovoid space of reflection. The vault is buttressed by five radial walls, which reach outward toward the campus. The compression ring of blocks reveals the keystone geometry of the arch. Though the vault appears to be in suspension, each block fits exactly against the others to transfer loads in pure compression. The exactitude of the fit required for this project prompted us to approach its fabrication from a new perspective: rather than designing instructions to follow, we designed an iterative behavior which allowed us to treat the material as an active variable throughout the process. We developed interactive design software that enabled feedback between geometry and structure in real time

Architect's statement

A memorial is not a commission that I ever wanted. It marks a tragedy. In the face of fear and terrorism, what can a community do? It can gather and reflect and re-affirm our values of openness and diversity. The memorial offers a space of reflection. Its curvilinear form highlights a conspicuous absence at its center. It is clear that something is missing, almost like a pantomime, defining the edges of a missing center. The central void is also a room that unifies the five other rooms formed by the buttresses. It also offers a metaphor for diversity and openness. Each stone is different and unique, and they are all necessary to work together to stand. Strength, a term used after the bombing, as in Boston Strong or Collier Strong, is here translated into a structural form: a vault. It is a beautiful way to show the interconnectedness and co-dependency of individuals relative to a community.

Contractor's statement

We don't typically get asked to build a solid stone arch structure, and certainly not one with a five-way keystone and buttress configuration. Needless to say, it was a unique project to work on. The challenge was really the erection sequence and the tight tolerances. Everything needed to be exactly in the right place because a 1/8" misalignment between stones could be amplified all the way through the memorial. We used continuous surveying of the stones to locate them in space. We also started from the keystone and worked our way out—a little counter-intuitive—so that tolerance could be "shed" from the interior to the exterior. When the scaffolding came down we all stood there—20 guys stood there for eight hours to watch 30 tons of stone not move at all, and it was the happiest day of my professional life.

"This is a great example of a holistic project that focused on innovative uses of process, technology, and materials." ~ Jury statement

Additional information

Project attributes

Year of substantial project completion: 2015

Construction documents phase: 8 months

Building area - acres: 0.145

Building area - Total Gross Square Feet (GSF): 6300

Cost: withheld

Project team

Concrete Placement: G&C Concrete Construction

Construction Labor: Liberty Construction

Construction Manager: Suffolk Construction

Electrical Contractor: Gaston Electrical Co. Inc.

Engineer - Civil: Nitsch Engineering

Engineer - Electrical: AHA Consulting Engineers

Engineer - Geotechnical: McPhail Associates

Engineer - Structural: Knippers Helbig-Advanced Engineering

Engineer - Structural Engineer of Record: RSE Associates

Geotechnical Construction Company: Hayward Baker

Granite and Field Surveyor: Feldman Land Surveyors

Granite Erector: Phoenix Bay State Construction Company

Granite Supplier (Quarry): Virginia Mist Group

Landscape Architect: Richard Burck Associates

Lighting Designer: Horton Lees Brogden Lighting Design

Landscape Contractor: Valleycrest Landscape Development

MIT Research Assistants: William Plunkett (SMBT ’15), Corentin Fivet (Post Doc), Euipoom Estelle Yoon (BSA ’16), Anna Kaertner (BSA ’15), Cecile Lu (BSA ’16), Marianna Gonzalez (Wellesley BA ’16)

Paver Supplier: Hanover Pavers

Site Development Contractor: James W. Flett Co. Inc. (excavation work)

Specialty Masonry Consultant: Ochsendorf DeJong and Block Consulting

Stone Fabricator: Quarra Stone Company, LLC

Typographic Consultant: Francesca Bolognini


Anthony Hauck, Chair, Hypar AEC, Waltham, Massachusetts

Phillip Bernstein, FAIA, Yale School of Architecture, New Haven, Connecticut

Desiree Mackey, GEI Consultants, Denver, CO

Sera Maloney, The Foth Companies, Lake Elmo, Minnesota

Natasha Luthra, Jacobs, Philadelphia, PA

Image credits


Iwan Baan


Iwan Baan


Iwan Baan


John Horner


Iwan Baan