This is the time of year tourists descend on Washington.

School groups. Teachers. Grandparents. Future Farmers of America, decked out in their blue, corduroy jackets.

And this excursion inevitably involves a pilgrimage to the U.S. Capitol.

I know because I work in the Capitol daily. And I wade through currents of people, teaming through the halls of Congress this time of year.

A throng of tourists bearing down on Washington in springtime is as ubiquitous as the cherry blossoms - minus the scraps of tiny pink leaves the wind broadcasts all around the city.

A procession of Gray Line tour buses filters through Garfield Circle on the Senate side of the Capitol. Someone else runs by with a Close Up Foundation pass flapping around their neck.

"Let's go! Let's Go! I'm hungry!" yells a man who appears to be a junior high school teacher. His masses of seventh and eighth graders suddenly snap to attention upon hearing a suggestion about food.

A family walks past on the sidewalk, pushing a child dressed in a tiger suit in a stroller.

I double check to make sure it's not former Rep. David Wu (D-OR).

Springtime is the time of year I'm called upon to lead tours.

Honestly, one of the most-rewarding parts of my job is giving a tour of the U.S. Capitol. No two of my tours are alike. I try to contour them to the ages of the people I'm showing around and gauge their interest and knowledge of history and government. The clock is always an important factor, too.

I can do a "cameo" tour in as little as 20 minutes if necessary. I actually gave a six hour tour once a couple of years ago. Someone along for the ride had all the time in the world and was intrigued by everything Capitol Hill had to offer. And I had the time to boot. You have to realize how massive the Congressional campus is - especially trekking between the Capitol itself and through the underground tunnels which link the House and Senate office buildings and the subterranean Capitol Visitor's Center (CVC). We spent hours inside the Capitol itself and a couple of other hours in the office buildings and an hour or so watching the House and Senate in session.

My tours aren't like the official ones given by the guides wearing "red coats" who roam the Capitol. They're not the same as what you'll get from a 21-year-old intern toiling for his or her home state Member of Congress. They're not like the ones a lawmaker will give after the Capitol's cleared out at night. And they're different from the one you'll get from my friend Steve Livengood, the Chief Guide of the U.S. Capitol Historical Society, either. In my opinion, Livengood is the best tour leader out there. I've learned a lot from him over the years. I'll never know as much about the Capitol as Steve has forgotten.

My tours aren't better than any of these. They're just a little different. So if you don't get to join me for a tour, here are a few things I like to show people when they visit the Capitol.

A Capitol tour will inevitably start in the CVC. It pulsates with tourists this time of year. If you're at the Capitol in the off-season, walk around Emancipation Hall for a few moments and look at all of the statues lining the walls. Emancipation Hall is the gigantic foyer which leads to the Capitol. Each state has two statues positioned somewhere in the Capitol complex. My favorites are Philo T. Farnsworth, a Utah inventor who was a pioneer in creating television. The statue depicts a beanpole Farnsworth holding a gigantic tube used in early television sets.

There's a statue of Helen Keller, representing Alabama and King Kamehameha, the monarch of the kingdom of Hawaii. King Kamehameha is hard to miss. A golden cloak ensconces this statue as he clutches a spear in his left hand. You can see the original casting of this statue in one version of the opening credits to the original Hawaii Five-O TV program.

But there's something worth checking out before you head upstairs to the Capitol.

Take a few moments to wander around the Exhibition Hall. There you'll find a lot of artifacts belonging to the Capitol as well as a polyurethane model of the Capitol dome. One side replicates how the dome looks on the outside. The other side is concave and represents the rotunda's innards.

But what I find especially interesting are six, built-to-scale dioramas of the Capitol grounds. The first dates back to the inception of the republic. When you enter the Exhibition Hall, turn to your right and go down to the end (the Senate side). There you'll find a diorama showing Jenkins Hill - which later became known as Capitol Hill - and the initial construction of the Capitol. In fact the original House and Senate sides of the building were linked by a wooden walkway, as there was no dome yet.

Then walk toward the House of Representatives side of Exhibition Hall and see the other five dioramas as you go. They show how the Capitol and the surrounding city grew. As you get to the 20th Century dioramas, you'll notice how the Supreme Court moved out of the Capitol and across the street. The Library of Congress, which was once the office suite now used by Senate Minority Leader Mitch McConnell (R-KY) evolved into three massive structures. And the Congress itself went from just using the Capitol, to adding six gigantic buildings to house Congressional staff and its members.

You'll also observe how the city of Washington matured around the Capitol.

One thing is clear about viewing these dioramas: the federal government and the Congress has grown geometrically. One can reach their own conclusions about the merits and demerits of that phenomenon.

A traditional Capitol tour will then usher you into the heart of the Capitol. The first stop is the Crypt, below the Rotunda. I always try to take my guests down to the House side near the Hall of Columns. There is where you'll discover a striking painting of the late Rep. Shirley Chisholm (D-NY). In the painting, Chisholm wears a white and blue print dress. Her arms are crossed with her right index figure raised as though she's about to tell you to "hold on just a minute."

In 1968, Chisholm became the first African American woman elected to Congress. Chisholm represented an urban district in Queens, New York. So it was only natural that the House assigned her to the Agriculture Committee.

Naturally Chisholm rebelled. Until she realized that she could actually use her misfit committee assignment to benefit her constituents.

All politics is local. And there are a lot of poverty-stricken people living in New York City. So working with farm state lawmakers like then-Sen. Bob Dole (R-KS), Chisholm used her position on the Agriculture Committee to expand the Food Stamps program. American farmers wanted to sell their commodities. And with government assistance, Chisholm believed she had a market for them. She also helped craft the supplemental nutrition program for Women, Infants and Children (known as WIC).

I escort visitors past the Chisholm painting because it's emblematic of the creativity necessary to succeed in Congress. No matter what hand you're dealt, there's always a way to accomplish your goal. It's just a question of how clever a legislator can be.

Chisholm summed up her approach this way:

"I want history to remember me not just as the first black woman to be elected to Congress. Not as the first black woman to have made a bid for the presidency of the United States. But as a black woman who lived in the 20th century and dared to be herself. I want to be remembered as a catalyst for change in America," she said.

There's another key stop on my tour. Time permitting, I usher my group to the big flight of stairs which runs down from the Crypt to the Terrace level of the Capitol. To the west, you can peer out the center door toward the National Mall, the Washington Monument and the Lincoln Memorial in the distance. It's the same door that President Obama and his predecessors walked through for their respective inaugurations. And either Mr. Obama or someone else will move through that same passage next January for their inauguration.

I usually make sure my guests are lined up in the center of the stairs so they can see directly down the center of the Mall.

And that's when most figure it out.

The Capitol is not exactly lined up with the Mall.

Take a few steps to the right, and all of a sudden everything comes into alignment. It's close. But despite the symmetrical appearance, the Capitol and the National Mall are in fact off-center.

That revelation has prompted more than one of my guests to proclaim that the catawampus configuration is an appropriate metaphor for Washington.

So it doesn't matter when you come to the U.S. Capitol. Whether it's this week, this fall or next year. All of this will still be here for your tour. Whether you're on board with me or someone else.

Even if things are a little catawampus.