On a recent summer Sunday, as hundreds of motorists hurtled down Route 93 toward Route 28 and the ferry dock in Woods Hole, two dozen Vineyarders hurtled in the opposite direction.

Up 28 and 93 we went, in a chartered bus, toward Boston.

We are members of the U.S. Slave Song Project Spirituals Choir. The Slave Song Project, founded by Jim Thomas, is dedicated to researching and educating the public about the songs sung by African slaves in this country between 1619, when the first kidnapped Africans were landed at Jamestown, and 1865, when the last slaves were finally freed at the end of the U.S. Civil War.

Led by Jim and his powerful bass voice, the spirituals choir brings the songs to life by singing them in libraries, schools, senior centers, churches, theatres and even restaurants. Since Jim is a seasonal Vineyard resident — he lives in Virginia when he’s not on the Island — our performance season usually lasts only from mid May to late August. When we boarded our bus Sunday morning, we already had a dozen presentations behind us.

Approaching Boston, cars and trucks moved at 60 miles an hour, as densely packed as if they were parked. On either side of the highway billboards incited us to Buy! Call! Click!

Our bus delivered us to a quieter, less crowded world. After singing at the 11 a.m. service at the historic Old North Church in Boston’s North End, we went on to the Royall House and Slave Quarters Museum in Medford, a remarkable place that brings the realities of slavery home in powerful ways.

The Royalls were the largest slaveholder in colonial Massachusetts. Isaac Royall Sr., a Maine native, became wealthy trading in sugar, rum and enslaved people. In the 1730s, when he moved his family to Massachusetts from their sugar plantation in Antigua, he brought with him at least 27 slaves.

The estate, originally comprising some 500 acres, was like a small, mostly self-sufficient town. Nearly all the work done to sustain it — cooking, cleaning, washing clothes and linens, gardening, orchard tending, horsekeeping, driving, carpentry, blacksmithery and so on — was done by slaves.

Before we sang, museum executive director Tom Lincoln, gave us a tour. The mansion’s furnishings and architectural detail, the paintings on its walls, speak of wealth. Tom told the stories that the house itself leaves out. Feeding the Royall family and its frequent dinner guests, for instance, took up most of every 24 hours. This is why there are pallets in the winter kitchen for the “staff” to sleep on between the end of one work day and the beginning of the next a scant few hours later.

The slave quarters — the only such building that has survived in the northern U.S. — are only a literal stone’s throw from the mansion. The proximity startled me at first. The tour underscored the paradox: that despite the chasm separating black from white, chattel from owner, day-to-day life threw the two together in many ways. In the dressing room upstairs, slaves would have dressed Isaac Royall, his wife Elizabeth, and their growing children. Manners were more formal in the 18th century, and clothing more elaborate. One needed assistance to dress oneself to go out, or even to go downstairs.

What the house slaves must have known about the family they served! But very little of what the slaves did or thought has come down to us. Often we know no more than their first names, and sometimes not even that.

We don’t know what songs the Royalls’ slaves sang either. Since many of them came originally from the Caribbean, they might not have had much contact with slaves in the southern colonies of what became the United States, where most of the songs we sing came from.

Still, as we sang — on a porch outside the main house, facing the slave quarters — we couldn’t help but imagine the enslaved residents of this place singing songs like Soon I Will Be Done, and We’re Gonna Sit at the Welcome Table. Some of the them might have accompanied the family to worship services in churches that looked much like Old North Church, and come home impressed with the Bible stories that grew into spirituals like We Are Climbing Jacob’s Ladder.

The Royall House and Slave Quarters, like the spirituals we sing, offers passage into the past and connection with lives whose details weren’t recorded. On the bus coming home after a long and richly rewarding day, I considered how many of the slave songs refer to journeys: the passage from Africa in Wasn’t That a Wide River, the wayfaring stranger “traveling through this world of woe,” and, between 1830 and 1860, escape on the underground railroad.

While the rest of the world traveled to Martha’s Vineyard, our bus took us into the 18th century. The river between now and then isn’t as wide as it looks.

Susanna J. Sturgis lives in West Tisbury. The Royall House and Slave Quarters is open to the public on weekends from June to October. For more information, see royallhouse.org. For more about the spirituals choir and the U.S. Slave Song Project, see usslavesongproject.com.