She did know. It turned out she worked with the very intelligentsia who are busy trying to thwart terrorism every day, and was more than happy to direct me past the tunnel, across at the lights, and around to the right.
I walked for what seemed like hours (but was more like 15 minutes) along the busy road when I came to a grassed hill across from Arlington Cemetery. I left the footpath and scrambled up to the brow to find the big concrete Pentagon building sitting alone in a massive carpark behind security fences in front of me.
Planes were landing at nearby Reagan National Airport and looked eerily like they were about to land on the building itself. This is the same side that the 9/11 planes hit so it was understandable that 5 years on from the terrorist attacks, the people of Washington are still jumpy, as I discovered.
I probably did look like a madwoman, possibly dangerous and certainly suspicious, standing on a grassy knoll taking photos of the building. I ignored the woman yelling at me to come down, pretending I didn't hear her shouting from the footpath that I wasn't supposed to be up there. But after a few more clicks of my camera I looked around and saw her dialling on her cellphone so thought I'd better get a move on and walked nonchalantly down to the nearby gas station.
From there the view of the building was a bit clearer so I walked to the fence and began clicking again. Still nothing much to see, but I'd come all this way
I tried to ignore the man who hollered "hello" a few times but his voice was coming closer so I feigned innocence and turned to say hello back to him. He was a burly black man who had pulled his empty school bus in for petrol and was clearly doing his citizen's duty by approaching the madwoman with the camera.
He told me I wasn't allowed to take photos and that the police would be coming any minute. I looked around quickly, hoping that would be the case - because there's nothing I like more than a bit of drama to write home about.
But alas, my time as a sneaky paparazzo passed without incident and I walked back to the Metro station with my photos safely intact deciding I needed to visit the International Spy Museum to really get the lowdown on the espionage and skulduggery in this city.
It's just one of many extraordinary museums in the capital of the United States which, it's worth remembering, was carved out of land donated by neighbouring Maryland and Virginia in 1791. It is not a state, but a federal district created specifically to serve as the seat of government.
Its second industry is tourism, powered by the hordes from around the world who come to gawp at the seat of global power, and explore the memorials, monuments and museums with which the city is studded. Even the White House and the Capitol double as tourist attractions.
Then there's the remarkable Smithsonian Institution, a collection of 18 museums, all with free admittance and housing some of the world's finest treasures. And there are many more museums, galleries and sights that make a visit to this city so exciting, not to mention cultured.
However a culture-vulture I am not so the International Spy Museum, with its interactive exhibits on espionage, was my first priority. Fans of the suave Mr Bond and lovers of surveillance will be excited about this place. In fact, James Bond's car is parked in one of the many rooms in this labyrinth of history.
My visit was made all the more exciting because I went with a former CIA agent. He and his family hosted me for a year when I was a wide-eyed exchange student, many years ago.
New Zealand had just become nuclear-free when I landed in Maryland for a year with AFS, and my new "dad" was head of counter-terrorism for the CIA. He needed special permission to host me. Our anti-nuclear stance wasn't a problem and I had a marvellous year.
We have visited more than 40 times since and today my hosts are retired grandparents living on the coast and looking forward to returning to the big smoke for a couple of days.
We start in the Spy City Cafe and order a Langley Dog (all-beef hot dog, chili, chopped onions and grated cheese), an MI-5 Dog (all-beef hot dog, crunchy onions, bacon and grated English cheese) and a Disguise Dog (basically my choice of anything). Afterwards we walk through the futuristic, blue-lit corridor and catch an elevator to the third floor where we each assume an identity and are charged with memorising as many details as possible.
I try spotting secret drop points and identifying dodgy men in a spy training video at a subway station. I'm not very good at this. I pore over the history of Cold War spy techniques with double-crossing agents and war-time starlets-turned-informants. On the way out I take a quiz about my "character". I fail miserably and am arrested.
No information about current spying methods is on display, but I suppose that makes sense for a city that's busy administrating a war on terrorism.
CHECKLIST
Getting there: Air Tahiti Nui flies direct to New York twice a week from Auckland, or four times a week with a stopover in Tahiti.
Getting around: Washington DC is an easy city to get around. In the many times I've visited I've never had a car, as the Metro, the underground subway system, and good old shoe-power have been more than adequate. Buy an all-day hop on-hop off subway pass to get to as many museums and memorials in the quickest time.
Where to stay: Park Hyatt in Georgetown is close to the shopping and nightlife in the hippest part of town. It has a Tea Cellar with rare vintage teas and the most zen-like bathrooms I've been in.
Courtyard Marriott at Capitol Hill is centrally located to the seat of power and to the Museum of the American Indian, the newest addition to the Smithsonian Institution.
Further information: The International Spy Museum is at 800 F Street, NW Washington.
For general information on visiting Washington see washington.org.
Megan Singleton flew Air Tahiti Nui and United Airlines to Washington DC.
