Drawings of butterflies, Arabic writing and scorpions now adorn what was once a barren highway underpass dividing two New Haven neighborhoods.

In an effort to reclaim bare concrete passageways and to bridge two New Haven communities, hundreds of volunteers painted murals under Interstate 91 this past weekend. Part of the Under 91 Project, over 400 people flocked to Humphrey and State Streets on Sept. 27 for a block party and mural painting. The event marked the first time in New Haven’s history that the city allowed a community group to paint a permanent mural on a state-owned underpass. The project organizers said they hoped the mural would help bridge the East Haven and Fair Haven neighborhoods, which are divided by the highway.

“It was an inspiring process,” project organizer Yonatan Landau SOM ’15 said. “It was the first time I had really seen the East Rock and Fair Haven communities come together.”

The Under 91 Project set out early this summer to install a mural that would permanently transform the barren stretch of featureless concrete under the interstate into an inviting public walkway.

In early March, project organizers — led by a group of Yale graduate students and New Haven community members — administered surveys to New Haven residents, asking their impressions on the underpass and what type of art they would like to see on its walls. Based on these results, the organizers solicited calls for artists to design the mural and then allowed community members to vote on their favorite design. By this weekend’s block party, the group had received over 20 submissions from talented artists, Landau said.

The winning mural design named “Bright Big Wall” was created by the collaborative team of local artists Damian Paglia, Alberto Colon and a graffiti group dubbed Hi Crew. At Saturday’s block party, community members had the opportunity to paint a part of the underpass wall.

Under 91 Project organizers said they hoped the mural and residents’ contributions to the artwork this weekend would liven the concrete wasteland underneath the highway.

Boris Sigal SOM ’14, a leader of the Under 91 Project, emphasized how dark and uninviting the highway was before this weekend’s event. Another leader of Under 91, Aicha Woods ARC ’97 echoed Sigal’s observation.

“The highway makes a very inhospitable passage even though it is a boundary that a lot of people have to pass everyday,” she said.

Woods also commented on the deep-seated social and economic divisions between East Haven and Fair Haven.

“The highway really makes a pretty brutal division line at the ground level through neighborhoods,” she said.

Landau added that most Yalies are unaware of what exists beyond the Interstate 91 underpass that connects Upper State Street and Jocelyn Square neighborhoods at Humphrey Street. He noted that most of his classmates do not know where his apartment is, even though it is only a few blocks away from key landmarks such as East Rock and the business school.

In spite of the divide between the two neighborhoods, the block party was a huge success, Sigal said, because hundreds of people from different neighborhoods in New Haven contributed to the wall by adding drawings and paintings. “The Block party was one of the most truly diverse and cross-over community events I’ve been to in New haven,” Woods said. “Credit for its success should go to the artists, to community for supporting it, and the hardworking volunteers.”

The Under 91 Project stems from the Inside Out project, an effort to post temporary black and white portraits in the same highway underpasses in 2012, Woods said. Like the Inside Out Project, the Under 91 Project is sponsored by the Urban Resources Initiative — a nonprofit organization supporting community development initiatives — and local businesses such as Artist and Craftsman Supply supported the event by donating thousands of spray cans. Despite the similarities between the two projects, though, Woods said that the organization and scale of the Under 91 project is unprecedented for the city.

“What is on the wall is truly incredible because of the diversity of language, expressions and positivity,” Woods said.

Due to its novelty, the process of gaining state-issued permission for this project was complicated, Woods said. The team of organizers had to acquire a temporary encroachment permit and maintenance agreement from the city in order to have the block party event, and Woods said organizers are still negotiating with the city to ensure that the mural can remain on the underpass indefinitely.

Organizers said they may add artwork to other barren underpasses in New Haven in the future.

Some of the artwork added to the wall this weekend includes Arabic writing, butterflies and scorpions.