What U.S. destination could offer more history than Concord and Lexington?  Here you can walk in the footsteps of many of the greatest thinkers and heroes of American History.

Paul Revere: 

One if by land, and two if by sea;
And I on the opposite shore will be,
Ready to ride and spread the alarm
Through every Middlesex, village and farm,
For the country folk to be up and to arm.

Paul Revere left Boston on horseback around 10 PM on April 18, 1775 after seeing the famous signal in the Old North Church telling him the British soldiers were on the way.  He rode to Lexington calling out his famous warning "The British are coming, the British are coming!"  At 1 AM, he, William Dawes and Dr. Samuel Prescott left Lexington for Concord.  Revere was captured in what is now Minute Man National Historical Park (which covers 900 acres in Lexington, Concord and Lincoln) - only Prescott got all the way to Concord.

At the Minute Man Historical Park you'll find the Old North Bridge (site of the battle where the "shot heard 'round the world" was fired), the "Battle Trail", The Hartwell Tavern, a restored 18th-century tavern which is now a "living history" center.

Henry David Thoreau (1817-1862):

At Walden Pond you can visit the spot where Thoreau's cabin was his home from July 1845 to September 1847.  There is also a replica of the cabin nearer to the road/parking lot.  (The walk through the woods to the original cabin site -there is no building there now- is well marked and not difficult, but plan on using up at least an hour to get there, spend time soak up the atmosphere and get back.)  There is a path that goes all the way around the pond - it's a great walk with many (not difficult) ups and downs. 

In summer, the pond is a great place to swim and have a day on the beach as well.  Some people swim (or fish) in the lake at various jump-off points around the path, but remember that the lifeguards are only at the main beach area. The parking lot fills up early, and the supplemental parking lot (on the other side of Route 2) is quite a walk, so plan on arriving before the crowds come.  There is a gift shop there as well.  Many people bring picnic lunches, since dining options are slim and if you leave the parking lot to drive into town to get lunch, you'll lose your spot.

Louisa May Alcott (1832-1888):

You can visit Orchard House, the childhood home of this famous author of "Little Women" and see how she and her family lived.  Her father, Bronson Alcott (1799-1893), was one of America's most influential educational reformers.

Ralph Waldo Emerson (1803-1882):

One of the finest thinkers and writers of early American history, Emerson was a preacher, philosopher, and poet.  A tour of his home where he lived from 1835 until the end of his life is a must for history buffs.