Boston has another advantage for the budget-conscious. Its public transportation system is cheap (we purchase 3-day unlimited "T" visitor passes for $18 each), and decipherable by an 11-year-old.

After scanning Boston from on high, we plunge down into the subway.

We are looking for the train to Park Street, but apparently I am not looking quickly enough.

"Can I see the subway map, Dad?" asks Cullen.

His brow wrinkles.

"Let's see … Green line to Park. And then, if we want to go on, maybe the Red line to Quincy Market."

Any parent knows it is only a matter of time before we are eaten.

Visiting Boston and ignoring the Freedom Trail - 16 nationally significant historic sites along a 2.5-mile walk make for the world's easiest history lesson - is like visiting Venice and ignoring the water. History is not always the primary interest of the young (Graham: "When can we swim in the hotel rooftop pool?"), but as a child my parents dragged me to mu­seums. Now it is my turn to get even.

Exiting from the Park Street station, we find ourselves at Boston Common. Bostonians love to eat ("Bostonians," crowed one info plaque, "are the biggest con­sumers of ice cream in the U.S."). There are restaurants everywhere, and where there aren't restaurants there are street vendors, their carts wafting the scent of everything from sweet Italian sausage to fried dough topped with custard.

The boys sample the latter.

It is my job to ask the stupid question.

"Good?"

Preoccupied with consumption, no one gives me an answer.

Boston bills itself as America's Walking City and it's true.

"It's safe and easy to walk all over the city," a local had told me earlier. "Plus, you don't even want to try driving a car."