In Boston, March 17 means two celebrations. Many people know it as St. Patrick’s Day. Fewer realize it is also Evacuation Day, a local holiday that marks the day in 1776 when British troops and ships left Boston after a long siege. It is one of the most important moments in the city’s history, and a wonderful story to explore with kids.
This guide explains what happened in simple terms and offers ideas for families, classrooms, and neighbors who want to learn more together.
The Story in Brief
By 1775, tensions between the American colonies and Great Britain had boiled over into armed conflict. After the battles at Lexington and Concord in April 1775, colonial militia surrounded Boston, where British troops were stationed. This began the Siege of Boston, which lasted for months.
The colonists had a problem: they did not have enough heavy cannons to force the British out. In the winter of 1775 to 1776, a young bookseller-turned-officer named Henry Knox led an effort to haul heavy artillery from Fort Ticonderoga in New York all the way to the Boston area. The journey covered roughly three hundred miles over frozen rivers, snowy mountains, and rough roads, using sleds pulled by oxen and horses.
In early March 1776, under the command of General George Washington, colonial forces quietly fortified Dorchester Heights overnight. Dorchester Heights overlooked Boston and its harbor. When British commanders woke up and saw cannons pointed down at the city and their ships, they realized their position was no longer safe.
After a period of negotiation and preparation, British troops and many Loyalist residents boarded ships and sailed away on March 17, 1776. Boston was free of British occupation, and the event became one of the first major victories for the American side in the Revolutionary War.
Why It Still Matters
Evacuation Day reminds us that history happened right on Boston’s streets and hills. It shows how planning, persistence, and teamwork changed the course of events. The Knox expedition, in particular, is a remarkable story of ordinary people doing extraordinary work in harsh New England winter conditions, something every Bostonian can appreciate.
Today, Evacuation Day is recognized as a holiday in Suffolk County, which includes Boston. A monument at Dorchester Heights in South Boston marks the site where colonial forces set up their cannons.
Explaining It to Kids
For younger children, try a simple version:
“A long time ago, soldiers from Britain were living in Boston, and the people here wanted them to leave. Some brave people pulled big, heavy cannons all the way from New York through the snow. They put the cannons on a hill overnight. When the soldiers saw them in the morning, they decided to get on their ships and sail away.”
Then ask questions to spark curiosity:
- “How do you think they moved cannons through the snow without trucks?”
- “Why would putting cannons on a hill make such a big difference?”
- “How do you think people in Boston felt when the ships left?”
Family Activities
Here are some ways to explore Evacuation Day together.
Visit Dorchester Heights
If you live in or near Boston, consider a visit to Dorchester Heights. Walk around the area, look out toward the city and harbor, and imagine what it would have looked like in 1776 without skyscrapers. Check official park information before you go for hours and accessibility.
Map the Knox Expedition
Using a library atlas or online map, trace the approximate route from Fort Ticonderoga to Boston. Have kids measure the distance and calculate how long it might take to travel at a few miles per day. Talk about the challenges of crossing rivers and mountains in winter.
Build a Model
Use cardboard, clay, or building blocks to make a model of Boston, the harbor, and Dorchester Heights. Place small ships in the harbor and “cannons” on the hill. It is a hands-on way to understand why the high ground mattered.
Read Together
Visit your local library and ask for children’s books about the Revolutionary War, the Siege of Boston, or Henry Knox. Librarians can recommend titles for different reading levels.
Write a Letter From 1776
Ask kids to imagine they lived in Boston during the siege. What might they write in a letter to a cousin? What would they see, hear, and eat? This builds empathy and creative writing skills.
Learning for Adults and Teens
Older students and adults may enjoy going deeper:
- Read about how the siege affected ordinary Boston residents, including shortages, divided loyalties, and families who left with the British.
- Explore how historians use letters, diaries, and maps to piece together events.
- Compare different perspectives on the evacuation, including those of Loyalists.
- Look for historical markers in your own neighborhood connected to the Revolutionary era.
Libraries and local historical societies are excellent places to find primary sources and well-researched books.
Celebrating Both March 17 Traditions
Because Evacuation Day and St. Patrick’s Day fall on the same date, many Boston families celebrate both. It is a natural opportunity to talk about how many layers of history live in one city: Revolutionary War history, generations of Irish immigrants who shaped Boston, and the many communities who call the city home today.
A family might start the day with a history walk and end it with a shared meal, music, or a soda bread tasting.
Quick Facts to Share
- Date: March 17, 1776
- Event: British troops left Boston after colonial forces fortified Dorchester Heights
- Key figures: George Washington and Henry Knox
- Key effort: Moving heavy artillery from Fort Ticonderoga to Boston in winter
- Today: A holiday recognized in Suffolk County, with a monument at Dorchester Heights
Quick check: What convinced British forces to leave Boston in March 1776?
- Colonial forces placed cannons on Dorchester Heights overlooking the city and harbor
- A snowstorm destroyed their ships
- They were called home for a holiday
Show answer
A. Cannons on the high ground threatened the British troops and ships, making their position unsafe.
