The story examines how a thriving community along Market Street was labeled incompatible with university goals and then reshaped by planning decisions in the mid-20th century.
In the 1950s and 1960s, planners set their sights on a corridor north of a major campus in West Philadelphia. They created “Unit 3,” declared blight, and used city mechanisms to clear blocks between 34th and 40th streets.
The University of Pennsylvania and partner institutions steered a redevelopment project that built the University City Science Center and a new high school. By 1967, about 2,653 people—roughly 78 percent from the existing population—were forced out.
This introduction frames an investigation that links policy, institutional power, and community impact in the 1960s. It uses archival records and oral histories to trace how a research hub grew while a neighborhood’s social fabric was erased.
Key Takeaways
- Unit 3 targeted a Market Street area in West Philadelphia for clearance in the 1960s.
- The university and allied groups guided the project that produced the Science Center.
- Official condemnation led to the removal of about 2,653 residents by 1967.
- Student activism in 1969 pressured institutions toward transparency and housing commitments.
- The case ties Cold War–era redevelopment goals to material harm to a long-standing community.
Origins Of The Black Bottom And Urban Renewal Pressures In West Philadelphia
Mid-century planners recast a lively Market Street corridor as a technical problem that needed clearing. That reframing shaped official reports and maps that treated social life as mere physical fixtures. Planners used narrow metrics to mark a zone for action, sidelining local ties and institutions.
From Market Street Corridor To “Blight”: How Officials Framed The Neighborhood
The city planning commission and redevelopment agencies labeled the area blighted. This label unlocked legal tools for condemnation and set the stage for larger urban renewal projects. Local voices were often discounted in technical reports.
Mapping The Black Bottom: 34Th-40Th Streets, Lancaster And Powelton Avenues To Ludlow
Oral histories confirm the mapped boundaries: 34th 40th streets, with lancaster powelton avenues to the north and Ludlow to the south. These precise streets grounded planning maps that would justify clearance.
Penn, Drexel, And The Push For “Compatible” Neighborhoods In The 1950s-1960s
University planners pushed for a campus buffer and sought neighborhoods deemed “compatible.” Scholarly work from university pennsylvania press documents how institutional goals and the west philadelphia corporation aligned to reshape a stable african american neighborhood. Early resident concern foreshadowed organized resistance.
For detailed archival context, see Collateral Damage: Unit 3.
Philadelphia Black Bottom Displacement By Penn Urban Renewal And Expansion Plans
The legal architecture for clearing Unit 3 rested on official labels and institutional coordination.

Unit 3, Blight Designations, And The Redevelopment Authority’s Legal Path
The City Planning Commission declared the blocks blighted, unlocking the philadelphia redevelopment authority‘s power to condemn properties within the defined footprint.
Unit 3 stretched from Lancaster and Powelton Avenues south to Chestnut Street between 34th and 40th streets. That proximity to campus made the area a priority for clearance.
The West Philadelphia Corporation As Penn’s Surrogate In University City
The west philadelphia corporation served as the operational agent for nearby institutions. Penn led the consortium that included local colleges and hospitals.
The WPC branded the conversion as creation university city, recruiting scientists and investors and steering redevelopment decisions. The sequence—designation, condemnation, transfer—moved residents from homes toward relocation while legal authorities completed property transfers.
| Actor | Role | Legal Tool | Outcome |
|---|---|---|---|
| City Planning Commission | Assessment & Designation | Blight finding | Triggered condemnation powers |
| Philadelphia Redevelopment Authority | Execution | Condemnation & Acquisition | Cleared properties in Unit 3 |
| West Philadelphia Corporation | Redevelopment Manager | Redevelopment agreements | Shaped University City and Science Center |
| Residents | Affected Parties | Notices & Relocation | Forced moves; community disruption |
Building The University City Science Center And University City High
A coordinated campaign in the early 1960s converted cleared lots into a prototype research district along Market Street. Incorporated in 1963, the University City Science Center became the core of that campaign. The plan aimed to recruit scientists, laboratories, and startups to a concentrated corridor.

Recruiting Scientists And Industry: The “City Of Knowledge” Strategy Along Market Street
The West Philadelphia Corporation pitched a research-driven project to attract R&D units and corporate labs. The science center was framed as the centerpiece to catalyze regional development.
- School and workforce link: A planned university city high would align education with technical careers and support the city science mission.
- Construction timeline: Late-1960s demolitions cleared streets for initial buildings, with first openings between 1969 and 1971.
- Early challenges: Recruiting major corporate tenants proved slow; the city science center adapted through partnerships and phased development.
Over time, expansions such as uCity Square consolidated the corridor into a dense hub. For deeper archival context on the project and effects, see the University City Science Center history.
Counting The Cost: Displacement, Relocation, And Community Trauma
Records show thousands of residents were uprooted as demolition crews prepared lots for new institutional projects. The official count for Unit 3 lists 2,653 people removed from an area west of 34th during the 1960s.

Who Was Moved And Where
About seventy-eight percent of the affected population were Black and mostly renters. Analyses attribute 666 people to the Science Center’s 26-acre site and 806 to the university city high footprint—together more than half of the total removals.
Clearing For Construction
Market Street west of 34th had been leveled by 1967 to ready parcels for the Science Center and school. The redevelopment authority executed condemnations, notices, and acquisitions that cleared blocks between 34th and 40th streets.
Human Impact
Oral histories capture the personal toll. Many relocated to Kingsessing in Southwest Philadelphia, fracturing family networks and local institutions.
“We watched our street vanish, then packed what we could and left,” recalled Andre Black about his removal from 36th and Market in 1968.
| Measure | Figure | Notes |
|---|---|---|
| Total Residents Removed | 2,653 | Unit 3 official count |
| From Science Center Site | 666 | 26-acre footprint |
| From School Footprint | 806 | University City High site |
| Primary Relocation Area | Kingsessing | Southwest neighborhood; major destination |
The disruption reached beyond housing. Churches, shops, and schools lost patrons and volunteers. Residents described trauma from witnessing bulldozers and the erasure of familiar streets. That loss reshaped community life in West Philadelphia for decades, linking institutional goals to real human cost.
Resistance, Accountability, And The Long Tail Of Renewal
When roughly 800 demonstrators seized College Hall, campus activism reshaped talk about research ethics and community harm. The action, led by students and allies, targeted university pennsylvania’s ties to the city science center and questioned contracts linked to wartime research.

1969 College Hall Sit-In: Student Activism, Research Ethics, And Housing Concessions
The sit-in forced concrete responses. The city science center board pledged no research that threatened human wellbeing. Trustees at university pennsylvania promised greater transparency in future development.
Pressure from students helped recover some land west of 39th Street for low-income housing. That pathway led, years later, to the University City Townhouses completed in 1982–83 as a partial remedy.
Legacy And Memory: Black Bottom Tribe, Historical Markers, And Calls For Reparations
Community memory kept the story alive. The Black Bottom Tribe organizes annual reunions and presses for a marker at 36th and Market Street. Advocates also ask for reparative measures such as educational access for descendants.
“We wanted more than apologies; we wanted lasting steps toward justice.”
| Actor | Outcome | Long-Term Effect |
|---|---|---|
| Students | Campus protest | Research pledges; policy scrutiny |
| University Pennsylvania | Transparency commitments | Promise of community engagement |
| Black Bottom Tribe | Memory work | Reunions; marker advocacy |
Conclusion
Conclusion
Mid-century decisions stitched a research district onto a long-standing neighborhood, reshaping streets and lives.
The formation of the science center and related university city projects built a new economic spine along Market Street. That development relied on the philadelphia redevelopment authority’s condemnations and a coordinated institutional consortium to clear the site between Lancaster and Powelton Avenues and 34th 40th streets.
At the same time, the loss of home and community—more than half of affected residents removed from key project sites—remains part of this history. Memory work, markers, and scholarship urge accountability so research-led growth honors past harms.
Readers who want fuller archival context can consult this essay on urban renewal and reflect on how city science, development, and neighborhoods might advance together with justice.
FAQ
What was the neighborhood known as Black Bottom and where was it located?
The neighborhood was an African American community concentrated between 34th and 40th Streets, spanning Lancaster and Powelton Avenues to Ludlow Street in West Philadelphia. It grew across the 19th and early 20th centuries as working-class residents, many connected to nearby industrial and institutional employers, built a dense, vibrant neighborhood of homes, churches, businesses, and social organizations.
How did city officials and planners justify redevelopment in the area?
Officials labeled large sections as “blighted” or physically deteriorated and argued that redevelopment would modernize the corridor, attract research and industry, and reduce overcrowding. Planning reports and the Redevelopment Authority used those findings to pursue clearance and new institutional and commercial projects that they said would serve the wider public interest.
What role did the University of Pennsylvania and other institutions play in neighborhood change?
The university and nearby institutions, including Drexel University, supported plans for a more campus-compatible neighborhood and economic development along the Market Street corridor. They partnered with civic entities and the West Philadelphia Corporation on land assembly and planning, influencing decisions about land use and priorities for the area.
What legal mechanisms enabled large-scale clearance of homes and businesses?
Municipal redevelopment law, blight designations, and eminent domain provided the legal path for land acquisition. Designations such as Unit 3 allowed the Redevelopment Authority to clear blocks for institutional projects and private development, often using condemnation to acquire title from owners and tenants.
Who was the West Philadelphia Corporation and how did it function?
The West Philadelphia Corporation operated as a locally based redevelopment agency that worked closely with universities and city planners. It acted as a surrogate for institutional expansion, coordinating land purchases, project proposals, and redevelopment plans intended to reshape the University City area.
What major projects replaced cleared sections of the neighborhood?
Significant new uses included the University City Science Center and facilities for a flagship high school, along with commercial and research-related buildings along Market Street. These projects aimed to attract scientists, industry partners, and students to a unified research and innovation corridor.
How many residents were relocated and where did most go?
Thousands of households were uprooted during redevelopment. Contemporary records indicate that a large majority of those moved were African American; many were relocated to neighborhoods such as Kingsessing and other West Philadelphia areas, while others dispersed across the region, disrupting long-standing community networks.
What were the immediate human impacts of clearance for construction?
Clearance forced families to find new housing, often with inadequate notice and limited relocation assistance. The loss of homes, churches, and shops caused economic hardship, social dislocation, and psychological trauma for residents who lost community anchors and social support systems.
How did residents and students resist or respond to redevelopment policies?
Resistance took many forms, including tenant organizing, legal challenges, and direct action. Notable episodes included student-led protests and sit-ins that criticized institutional responsibility for housing loss, demanded better relocation terms, and sought accountability from universities and redevelopment agencies.
What efforts preserve the neighborhood’s memory and seek redress today?
Community organizations, historians, and descendants have worked to document the neighborhood’s history through archives, oral histories, and markers. Advocacy for reparative measures and institutional acknowledgment continues, with calls for commemorative efforts, community-led development, and restorative investments in affected neighborhoods.
Where can researchers find primary sources and historical maps of the neighborhood?
Researchers can consult municipal redevelopment records, Redevelopment Authority files, university archives (including institutional planning documents), Sanborn maps, local newspapers from the 1950s–1970s, and oral-history collections held by local historical societies and university libraries.
How did the creation of the science and research corridor change local land use and demographics?
The corridor shifted land use from dense residential to institutional, commercial, and research facilities. That change altered the neighborhood demographic profile by displacing long-term residents and attracting students, faculty, and corporate tenants, producing long-term shifts in housing markets and neighborhood character.
What lessons do planners and universities cite from this period today?
Contemporary planners and institutions often cite the period as a cautionary case on the social costs of aggressive clearance. Lessons include prioritizing community engagement, investing in affordable housing, ensuring just relocation practices, and balancing institutional growth with protections for existing residents.
