We stroke northward, passing the New England Aquarium, and docks and wharves once the center of Boston's commerce. Boston bills itself as America's Walking City; it is equally compact by water. In less than 10 minutes, the Financial District disappears off our sterns, segueing to the North End. Here, we veer away from shore, out into the center of the harbor, which affords us Boston's full imprint.

We bob, awash in brine and history. In a single 360-degree sweep I see white-steeple churches, silent stone monuments, towering scions of modern day commerce, and 18th-century frigates of war.

Another beauty of water - not often do you suffer an impeded view.

"The old North Church, the Watch­tower, the Prudential Tower, the USS Constitution, Bunker Hill," nods Estey. "Isn't it beautiful?"

Passing through the locks that allow passage from the inner harbor to the famed Charles River - water rising, gates slowly swinging wide in King Kong fashion - we glide past the Museum of Science and into the Charles. Again we are enwrapped, and yet apart. On one side, the banks of the South End, Beacon Hill, the gold-domed Massachusetts State House, and Back Bay; across the way, East Cambridge, Kendall Square, and MIT.

"We paddle down here every Fourth of July to listen to the Boston Pops and see the fireworks," says Estey as we stroke past the Hatch Shell amphitheater, famed home to concerts on the green.