It was only in college that I realized that not everyone wakes up in the wee hours of the morning on the third Monday in April to see a reenactment of the Revolutionary War. As a kid, I watched as people exclaimed, “The British are coming!” while men dressed in red coats (including my pediatric dentist) marched down Main Street in Lexington and onto the Battle Green for a historical show down. These past few years in New Haven, I haven’t had this opportunity — and one might add, perhaps I have outgrown it — as Patriots’ Day is not a holiday in Connecticut.

Nevertheless, today, Massachusetts and Maine will celebrate Patriots’ Day. The Red Sox will play their annual 11:05 a.m. game at Fenway Park. Twenty thousand runners will climb up Heartbreak Hill during the Boston Marathon. And yes, the British will march onto the Battle Green in Lexington and across the Old North Bridge in Concord. Young and old alike will celebrate the 235-year-old memory of the shot heard ’round the world. And I will be reminded why I became a history major.

History in the United States is accessible though our monuments, parks and reenactments. On family trips, I always tried to squeeze in a visit to a presidential home. My family traveled to the usual places — George Washington’s Mount Vernon and Thomas Jefferson’s Monticello — but also visited James Monroe’s Ash Lawn-Highland and Teddy Roosevelt’s Sagamore Hill in addition to his Cabin in North Dakota. Once, on a trip to Ohio, we even stopped off to see James Garfield’s Lawnfield.

My grandmother gave us national park stamp books, which we brought everywhere —our trips out West to places like Mount Rushmore and Badlands National Park and the more local Minuteman National Park and Cape Cod National Seashore. Though I stopped collecting stamps when I was in seventh grade, my affection for the parks — and the visionaries we have to thank for them — has lasted. I suppose growing up down the street from the Old North Bridge and reading “Walden” at a high school a short walk away from Walden Pond can have that effect.

Frequently called “America’s best idea,” the National Park Service has a long history in our nation. In 1872, President Ulysses S. Grant designated Yellowstone the world’s first national park. Five years later, two civil war battlefields and Yosemite were added and in 1916, President Woodrow Wilson signed the National Park Service Organic Act, creating a congressional agency to “conserve the scenery and the natural and historic objects [and] to provide for the enjoyment of the same in such manner and by such means as will leave them unimpaired for the enjoyment of future generations.”

And this generation enjoys our national parks. Attendance is on the rise: There were 10 million more visitors last year than in 2008 — just two million short of the record, 287 million, set in 1987. This year, the record may fall; as part of National Park Week, the Park Service will waive entrance fees for all 392 parks.

Yet, many of these parks still face significant maintenance and protection challenges. Though President Obama launched the Great Outdoors conservation initiative on Friday, the Park Service currently estimates that it will need $9.5 billion in additional funds to complete a series of necessary repairs and improvements. In addition, there are many areas vying for designation as a National Park.

As we approach the centennial of the National Park System, we should renew our commitment to these important resources, which reflect American greatness at its best. Like Patriots’ Day, national parks do more than educate — they remind us of our place in history by showing us where we come from. Patriots’ Day parades and national parks are democratic, in the best sense of the word — created by the people, for the people. As Wallace Stegner wrote, “they reflect us at our best rather than our worst,” celebrating important places in the land of the free, home of the brave.. And they preserve more than memory: They preserve place — a feature that cannot be re-enacted. They bridge the gap between national greatness and the natural world.

National parks encourage family, adventure and exploration — they give meaning and color to national greatness. They can be justified without statistics, scientific claims or promises of jobs creation (though many presidents have used the National Park Service to employ Americans).

And beyond the history they tell, national parks teach people what is important in life and how to protect it.