A red brick line set into the pavement leads two and a half miles from Boston Common to the Bunker Hill Monument in Charlestown, passing sixteen of the city's most important colonial and revolutionary sites along the way. The full walk takes a good three hours — longer if you go inside the Old State House, the Old North Church, and Paul Revere's house — but you can do any portion of it and get something out of it.
The path is well marked but not always obvious: it crosses streets, ducks through alleys, and disappears under cobblestones for short stretches. A free map from the Visitor Center on the Common helps. Costumed guides lead 90-minute tours from the same spot; the tours cover the Common-to-Faneuil-Hall portion only, leaving the more demanding walk to Charlestown for the visitor to do alone.
Wear comfortable shoes — much of the trail is on uneven brick — and break it into halves over a day or two if you have the time. The North End makes a natural lunch stop.