Most locals don’t know exactly how long it’s been here. They say at least 300 years.

It was around before any of the buildings that stand today in this city of 134,000 on the Chesapeake Bay, preceded only by the Powhatan people — the native tribes and the plants they cultivated.

Born of a single seed, its trunk is now 16 feet around with a 100-foot-wide canopy that, at its height, soars 50 feet. A small studio apartment would easily fit under its shade.

In Hampton, where colonial and Civil War markers abound, the tree is perhaps one of the best-known, if sometimes taken for granted, reminders of history.

It’s where abolitionists — in the midst of the Civil War — secretly taught blacks from the Tidewater region to read and write. On a winter day in 1863, enslaved people flocked to it to hear the first Southern reading of the Emancipation Proclamation. The war would go on for more than two years, and freedom from bondage, if not discrimination, would not reach Texas — the Confederacy’s last stand — until 1865.

This year, the Hampton Roads region is observing the 400th anniversary of 1619, a year that marked the arrival of the first enslaved Africans to the English colonies just miles from the grand old oak. And the tree — a symbol of a more joyous moment in time — is also attracting greater attention and a growing number of visitors.

More tour groups are adding it to their itineraries. African American genealogists, who seek out southeastern Virginia archives amid ancestry research, pause in front of its swooping branches each day. During a recent fundraiser, Hampton University alumni held a “crab and craft fest” by the tree, whose image appears on a university logo.

President Trump mentioned the tree this month while speaking to leaders of historically black colleges and universities.

“In 1861, a free African American woman, Mary Peake, taught 20 students under an oak tree near a Union base in Virginia. That tree still stands tall and mighty on the campus of Hampton University,” Trump said. “Good school.”

Today, the Emancipation Oak rises on the far eastern edge of Hampton University, pushed up against an Interstate 64 ramp and protected by a short half-circle metal fence and a withering marker on one side and tall pine trees on another.

Itwas just months into the Civil War in 1861 when Union leaders declared that slaves who reached Union lines would not be returned to their Confederate owners and instead be considered “contraband” of war since they came from a self-proclaimed foreign land. While Virginia was Confederate territory, the Union held Ft. Monroe, a barracks on a peninsula at the tip of Hampton.

Enslaved people rushed to reach the fort in search of freedom. It wasn’t long before a camp of freed slaves formed on the outskirts of the military base, in present-day Hampton.

On Sept. 17, 1861, Mary Peake taught her first class for about 20 of those formerly enslaved African Americans under the tree. A free black woman who worked for the American Missionary Assn., she defied Virginia law that banned the education of free and enslaved African Americans. Peake got her own building, Brown Cottage, that would eventually grow into Hampton University, a private university that enrolls 3,672 undergraduates today.

“That tree is integral to Hampton University’s history, to the city’s history as a whole,” said Cassandra Newby-Alexander, a Norfolk State University history professor.

On a recent muggy, rainy summer day, a mother and her teenage daughter stopped by to reflect on history.

“It draws you closer to your ancestors,” said LeShaun Martin, 56, who stepped up slowly to the lower branches with her 15-year-old daughter, Grace. From Pittsburgh, they were staying with family friends who suggested a visit. As African Americans whose ancestors were enslaved, for them the tree’s existence was news. They took out their phones and posed for selfies, smiling.

“Everything possesses the spirit of its time,” said Martin, whose mother grew up nearby in Isle of Wight County. “Hopefully, it will generate something that will bring a stronger connection to family.”

Moments later, Chad Tyson, who parks his blue BMW each day near the tree to attend courses at Hampton University, walked over to pause and reflect under its leaves in a daily ritual.

“It’s always on my mind,” said Tyson, a 47-year-old African American who is earning a doctorate in business leadership and administration. “We have to recognize what our ancestors did. What they sacrificed so we can be here.”

To some, the tree is just a tree. The same day, six teenage boys who were in town from Baltimore for a basketball tournament pulled up to the lot with their parents. They ran past the oak to the street corner, where Emancipation Drive meets William R. Harvey Way. They wanted photos with the “Hampton University” signs that welcome visitors to campus. The tree didn’t register with them.

The tree, a “living oak” that has green leaves year-round, has largely lived a quiet, uninterrupted life over the years. In 1974, it — along with Hampton University — was added to the National Parks Service list of historic landmarks.

The National Geographic Society also named it one of the “10 Great Trees of the World,” and researchers have tried to clone its DNA.

In 2010, when President Obama delivered a commencement speech at the university, he was given a seed from the tree to take to the White House. The sapling was placed on the South Lawn near a magnolia tree that President Andrew Jackson planted in the 1830s.

The oak faced one of its biggest challenges three years ago, when state authorities tried to go forward with an expansion of Interstate 64, which runs 75 feet from the tree. University officials protested, saying the construction would encroach on their campus and add to pollution around the tree.

They won, though the oak still faces enemies these days it can’t avoid.

Trash is sometimes littered under the canopy. Lower branches near the ground can get overrun by weeds. One in particular, an invasive vine called porcelain berry, has white flowers and teal, violet and green berries. Appealing to the eye at first, it grows rapidly to take up more space than it deserves.

Still, the oak survives.