10/11/2011 08:42 am ET Updated Dec 11, 2011

D.C.'s Top Rallies, Protests And Events: Using Metro As A Measure (PHOTOS)

WASHINGTON -- While the Occupy DC and "Stop the Machine" protests in the nation's capital have received plenty of media attention, they haven't quite yet measured up to demonstrations of years past in terms of sheer numbers. Last week in New York City, more than 15,000 protesters marched through Lower Manhattan as part of the ongoing Occupy Wall Street protests.

The demonstrations in D.C. -- which started Oct. 1 in McPherson Square with roughly 30 people and bolstered on Oct. 6 by the addition of the "Stop the Machine" protests in Freedom Plaza -- have been generally measured in the hundreds, not thousands.

Since these new demonstrations are ongoing -- on Monday, the U.S. Park Police extended the protest permit for Freedom Plaza by four months -- it's hard to gauge their strength as one-time events. For years, Metrorail ridership has been used as one rough measure for the size of protests, rallies and other events where mass matters as a sign of strength and impact. (The National Park Service ceased releasing crowd estimates for events after a lawsuit challenging its numbers for the Million Man March was filed, though President Obama's inauguration was an exception.)

In 2009, when Tea Party activists claimed that more than 1 million of their followers had gathered on the National Mall, those estimates were quickly debunked by simply comparing Metrorail ridership numbers from the day of the particular event to the same day the year before. By that measure, the Tea Party attendance came in closer to 70,000 people, which totally eclipses the ongoing D.C. protests.

Here's a look at a sampling of Metro's more remarkable ridership records and the events that helped pack rail cars.