What about Mary? The gravestone of 3-year-old Mary Hillhouse Oswald preserved in Center Church on the Green's crypt. When the city unveiled a proposal to build a fountain and a ​“children’s garden” on the upper half of the New Haven Green, Nicholas Mignanelli had a question: What about the eight to ten thousand people buried inches beneath the ground?The modern-day upper Green -- for now. As Center Church on the Green’s moderator and historian, Mignanelli spends a lot of time thinking about an oft-forgotten layer below the surface of the New Haven Green: the shallow graves of New Haveners from centuries ago.As the city sets its sights on the future of the central square, Mignanelli wants the long-gone New Haveners buried in the Green’s upper half to be considered.Since graves are thought to exist several inches below the surface, he’s concerned that even light construction could disturb the people buried there — as in 2012, when a tree knocked over by Superstorm Sandy unearthed bones.“This is an archeological site,” he said. “We’re talking six inches under,” added Center Church Reverend Ashley Cleere. ​“There’s a concern about being respectful. Burial grounds are a place to reflect.”The Green is legally owned by a self-perpetuating, five-person group called the Committee of the Proprietors of the Common and Undivided Land in New Haven, aka ​“the Proprietors.” The Proprietors have collaborated with City Hall, enlisting the landscape design company Tavella Group, to kick off public feedback on a proposed redesign of the city’s central square.Current sketches for an overhaul of the Green envision a cafe with a bathroom, a permanent stage, and temporary ice rink and game spaces on the lower half of the Green. The plan calls for a curved ​“woonerf” — a shared street that prioritizes pedestrians (akin to the twisty section of Audubon Street) — for where Temple Street currently divides the park. And they outline new ​“gathering nodes,” artistic plantings, a ​“children’s garden,” and an ​“interactive fountain” for the Green’s upper half.In the design process, the city is accounting for the park’s role as a cemetery, said City Engineer Giovanni Zinn. He noted that the designs for the Upper Green are being planned to minimize ​“digging or creating a subsurface disturbance.”When building, the city will use archeological technology like Ground Penetrating Radar to ​“ensure that … we can see exactly what’s there,” Zinn said.Still, the proposals for the Upper Green are what Mignanelli and Cleere hope to rethink with the burials in mind. There’s no record of burials in the lower Green, but according to Mignanelli, a large though undefined portion of the upper half of the Green between Temple and College Streets. “We don’t know where the bodies are buried — literally,” he said. Most of the area’s gravestones were relocated to the Grove Street Cemetery in 1821. Center Church continues to preserve dozens of remaning grave markers in its ground-floor crypt — a portion of the Green that already functioned as a cemetery when Center Church was built. According to Mignanelli, visitors have come to New Haven from across the country to learn more about their ancestors buried here.The known buried figures both within and outside the crypt include prominent names in New Haven’s Colonial history, including the regicide John Dixwell, former New Haven Colony Gov.Theophilus Eaton, Mayflower colonist Isaac Allerton, Center Church Rev. James Pierpont, and the grandmother and great aunt of U.S. President Rutherford Hayes. Also buried in the Green is Jethro Luke, whom the Pierpont family enslaved, and who eventually found freedom. He became one of the church’s first Black members and one of the city’s first Black property owners. (Recent local history efforts have shed more light on the Black people whom Eaton and Pierpont enslaved.)The Green is also thought to be the resting place of an uncountable number of New Haven residents who died in wars and epidemics such as smallpox. Many were likely buried secretly in mass graves. There are many children, along with women who died during childbirth, in graves both marked and unmarked.Mignanelli estimates that the total number of bodies in the Green could be up to 10,000. Protecting those graves is important out of respect for the theological beliefs of those buried, many of whom were Puritans who believed that the dead would come back to life during the Second Coming, noted Cleere and Mignanelli.“The people who built this church [above the crypt] did so because they believed that the people buried downstairs would someday rise and come upstairs to this church,” Mignanelli said.“Reverence for the dead is so cross-cultural and cross-theological,” he added.Both Cleere and Mignanelli said they support ideas for enhancing the Green to welcome more concerts, commerce, and child-friendly activities — especially on the Green’s lower section, which seems to never have been a graveyard. But they stressed that the park’s role as a cemetery makes it a site of collective memory at the heart of the city.Cleere imagines the upper Green as a place of ​“reverence,” ​“contemplation,” and ​“serenity.” “This was the intentional space that the community set aside” as a burial ground, Mignanelli noted. In his view, the park is an opportunity to root New Haven in its own history — with honesty about the pain and exploitation inextricable from the city’s foundations.“We think a playground would be wonderful,” he added. ​“Maybe on the lower Green.”City Engineer Zinn noted that the Green has taken on many roles over the course of history. ​“There are a lot of things that happened on the green, much like they do today. It was where everyone went to Church on Sunday and it’s where they buried their dead, and it was where animals were grazing, and all sorts of different activities.” He expressed openness to the Church’s ideas. ​“This is really the sort of conversation we want to start,” he said. ​“How can we remember those people and make more clear all of the people that are buried there?”Regicide Dixwell's grave — the sole stone preserved outside of the church's crypt. Nicholas Mignanelli gives a tour of the Church's crypt. Church Historian Nicholas Mignanelli and Rev. Ashley Cleere.