I am obviously somewhat of an idiot because it seems that many many cars on the road have "climbed Mt. Washington." Can someone tell me what it is about this since I have seen them on every kind of car from 2 doors to minivans?!

There is a toll road to the summit of Mt. Washington. I'm assuming that you get the bumper sticker as part of the fee you pay to drive up the mountain. I've never driven up (only hiked), and the view from the top is spectacular!

It is nice. But I am more impressed by those cars that have been driven to the top of Pike's Peak and Mount Evants -- both well over 14,000 feet in elevation.

There are 2 Mt. Washington's that I know of. One is in New Hampshire and the other one is in Vancouver Island, above the Comox valley alongside British Colombia's oldest provincial park, Strathcona.
The one in New Hampshire is the New England's most impressive summit. The Northeast's highest peak will captivate you with its remarkable views of the Presidential range, the White Mountain National Forest and beyond. The route, the views and the magic of this mountain sanctuary have remained largely unchanged since travelers began winding their way up Mt. Washington in 1861. This road to the sky was an unprecedented engineering achievement and remains the first man-made attraction in the United States!Breathtaking vistas reveal themselves around every bend of the 8 mile path to the top of New England. When the adventure of your ascent has been completed, a variety of experiences can be found on New England's highpoint. The Sherman Adams State Park Building, the Mount Washington Observatory Museum, and beauty and serenity awaits your exploration.
Now a bit of info about the other Mt. Washington in British Colombia, Canada.
Summer on Mt. Washington offers you a chance to experience the beauty of Vancouver Island's high alpine region.
On a clear day, the view from the top of Mt. Washington is breathtaking. To the south west is the Comox Glacier and Mt. Albert Edward.

The view to the east includes the Strait of Georgia, the coastal mountain range and the towns of Courtenay, Comox and Campbell River.

Mt. Washington is famous for its plentiful and consistent snow base in the winter months, but it blossoms in the summer months with a variety of activities and special events.

You can enjoy hiking, mountain biking, horseback riding, dining in small lodge restaurants, shopping in Gift Shops and of course the Scenic Chairlift Ride to a mile above sea level.

Walking trails are superb with great access into the vast network of trails in Strathcona Provincial Park, with opportunities to see deer, bears, Jacka sses, and a variety of pretty birds.

Shannon: To drive your own car to the peak of Mt Washington (N.H.) is a feat, and certainly deserving of a bumper sticker to brag about it. Most people (including us) choose to ride up in vans with experienced drivers. The road up is very scary, comes extremely close to huge dropoffs, with nary a guard rail in sight. Once you have made the committment to drive it yourself, there is no turning back. Rescue workers sometimes are called upon to retrieve panicked drivers who dare not go any further. As other posters have noted, the scenery atop Mt. Washington is spectacular. There is also a cog railway one can take to the top. Enjoy it - we did!