At evening rush hour along Garden street in Cambridge, I watched skateboarders, bikers, and walkers hustle along the edge of Cambridge Common, taking little notice of a small stone marker at the edge of the grass. 

When Cambridge resident Dan Geisz ambled past, I flagged him down for a quick conversation:

Me: So how often to you walk past here?
DG: Just about every day for work.
ME: This commemorative stone, have you ever noticed it before?
DG: I've noticed it, I've never read it to be honest. 

This is not a knock on Mr. Geisz. I myself have passed by here more than a few dozen times without ever even seeing it. But this is Eastern Massachusetts, after all, where any old rock, stone, or little patina-laden plaque might just mark a turning point in American history.

This one commemorates the site of one of the most crucial deliveries in American history, when Henry Knox provided George Washington the means to win his first battle as a general, and liberate a Boston under siege.

About a half-mile east of the marker stands a pale yellow mid-Georgian house. Today, it's a national historic site, perhaps more well known for being the home of celebrated American poet Henry Wadsworth Longfellow in the 19th century. But in the winter of 1775-76, it was the administrative and command headquarters of the new Continental Army and its first Commander-in-chief, George Washington. Think of it as the Department of Defense, the Pentagon, and West Point all rolled into a single, stately manse. 

Longfellow House, which served as Washington's Headquarters in Cambridge.
Garrett Cloer/NPS

Washington was a first-time general when he took up residency here, where I sat down with current head park ranger Garrett Cloer in the very room that once served as a 43-year-old Washington's office. 

"The most men [Washington] had ever commanded in his life prior to coming to Cambridge was about 1,400 men back in Virginia," explained Cloer. "He’s now responsible for somewhere around 10 times that number of soldiers. No one had ever taken anything on like this in the Colonies."

Boston was under British occupation, and the deadly 1775 Battle of Bunker Hill had done little to change that. Worse, during the battle the Colonial forces had lost five of their six field cannons – crucial weapons in a war against the far more powerful British force.

"So, Washington was not impressed by the people Massachusetts had put in charge of the artillery so he was looking for someone else," said Cloer.

Enter Henry Knox: A self-taught, ambitious young bookseller from Boston, eager to get into the fight.   

"He was not a soldier," said Cloer. "When he first meets Washington, he had volunteered to layout fortifications down in Roxbury."

Knox would forge a fast friendship with Washington, visiting him frequently – even dining with him – at the headquarters.

"He clearly catches Washington’s attention and seemed to be someone Washington liked to be around," said Cloer. 

And trusted. Months earlier, American militia forces led by Ethan Allen and Benedict Arnold had captured two British forts in upstate New York, and with them, a cache of cannon and other heavy weapons. Washington wanted them, and he enlisted Knox to get them for him.  

"Washington is entrusting this 25-year-old kid, essentially, to not just figure out a way to bring these cannon but also interact with this major General in Albany," explained Cloer. "And all of this without actually being officially part of the Army."

Artist rendering of Henry Knox bringing artillery.
National Archive collection number: 111-SC-100815

Knox would not disappoint. Knox and his men would secure the heavy weapons and, over three winter months – with oxen, horses, sleds and their own hands – deliver 50-plus tons of them across the rugged New York and Massachusetts landscape, including over Lake George and through the Berkshires.

"This is heavy manual labor," said Cloer. "It’s thawing and freezing. They're [getting] stuck in mud. There are times when these frozen guns fall through the ice and they have to retrieve them."

In late January of 1776, Knox and the weapons finally arrived in Cambridge. Of the 59 heavy guns Knox left New York with, 58 were delivered intact. Washington’s new army was in business. It was, in Cloer's words, "a very big deal."

It was these weapons that General George Washington would move onto Dorchester Heights under the cover of dark in March, finally forcing the British to evacuate Boston on March 17, 1776, handing Washington his first victory as a general.

It was a crucial early victory for a general – and a country – still finding their legs, and one that Cloer says we’d be wise to remember was far from inevitable.

"These were people doing these things," he said. "They were not mythical figures. They didn’t know they would successfully get those cannon here, they didn’t know they would end up breaking the siege of Boston. And I think it’s very important for us to look back and say they did these things, we can accomplish great things still today."