The New York City event is a Liberty Walk to be held on Sunday, September 12, from 3:00 PM to 8:00 PM, starting from St. Peter's Church at the corner of Barclay Street and Church Street in downtown Manhattan.

The Washington, D.C. rally is sponsored by a coalition including United for Pluralism, Muslims for Progressive Values, and Responsible for Equality And Liberty.

The New York City march is sponsored by Religious Freedom U.S.A., a group founded to support the Cordoba Initiative against the recent anti-"mosque" furor.  According to an email I received from Religious Freedom U.S.A., its founders are Joshua Stanton, Editor in Chief at the Journal of Inter-Religious Dialogue, and Frank Fredericks, executive director of World Faith: The Interfaith Service Network.  Its partner organizations include World Faith, Faith House Manhattan, Intersections International, and the Interfaith Center of New York.

The website for the Washington, D.C. rally contains the following observations about a recent wave of bigotry against Muslims:

On September 11, 2001 - nine years ago, America was attacked by those who killed Americans of every identity group and every religion - and who sought to divide and terrorize the United States of America.  New York City and Washington DC were attacked, but also one plane, Flight 93 that was hijacked to attack the White House or the Capitol building - was stopped - by Americans  that refused to give in to fear and terror.

Today, there are those who once again seek to spread fear and divide Americans on September 11. In Florida, one group seeks to burn Qur'ans on September 11, 2010. We have seen from coast-to-coast, from California to Florida, a series of protests against those who seek to freely worship in Islamic mosques, in California, in Tennessee, in Wisconsin, in North Carolina, in Kentucky, in Florida, in Connecticut, and throughout New York.  In Florida, we have seen a pipe bomb attack on a mosque, in Texas a children's playground in a mosque was burned down, while children are harassed, in Tennessee mosque properties have been vandalized and people have been convicted of arson attacks on mosques. On our national airwaves and media, we see and hear those who  call for  bomb attacks on mosques, and those who seek to spread open intolerance and hatred.

The rally itself is described as follows:

On Saturday, September 11, 2010, in Washington DC's Freedom Plaza at 2 PM, Americans of diverse religions, races, and backgrounds will join together in solidarity on behalf of our Constitutional freedoms and our universal human rights, including our freedom of religion, freedom of worship, and freedom of conscience for all people.

... We need you to join us in solidarity in support of our shared Constitutional freedoms and universal human rights. It is time for us to stand up publicly for the truths that we hold self-evident, as Americans and human beings. We are not afraid and we will not be divided.

We are inviting interfaith groups and human rights leaders to join us, and we will update this web page with our event supporters. But who we need the most is for you to join us, not because of your group or your religion, but as a fellow human being and a fellow American. We need you to help us show the world that  America can still be the land of the free and the home of the brave - not just for some Americans, but for all Americans.

More details about the rally in Washington, D.C., including driving directions, can be found on the rally's home page.  (There is also a Facebook event listing for the rally.)

The New York City march organizers have the following very specific instructions for those who would like to participate:

Greeting Fellow Supporters of Religious Freedom,

We are pleased to announce that Religious Freedom USA is leading a demonstration in support of Park51. We must support the religious freedoms that are at stake for all Americans. Please share this with everyone you know who support religious freedom:

The Liberty Walk: Interfaith Rally for Religious Freedom

...

Sunday, Sept. 12, 3pm

Starting at St Peter's Church

Church ST and Barclay

We will walk from St Peter's Church to a synagogue (TBD), World Trade Center, and finish at Park51. Please be respectful and mindful. We won't allow any signs at this demonstration. Rather, we ask everyone to bring a flag to the demonstration as a reminder of religious freedom.

Note especially those last three sentences, if you are planning to participate.

The announcement also contains suggestions on how to help out and spread the word.  Note their request that supporters contact them.  Those who wish to get more heavily involved may want to Join the Liberty Walk Action Team, or perhaps intern with them.

(Another copy of the announcement can be found on Facebook.)

Everyone, please help spread the word about these events to everyone you know who cares about religious freedom for all.

P.S.:  My own group, New Yorkers Against Religion-Based Bigotry (NYARBB), will be participating in the New York City Rally for Religious Freedom, but has no organizational affiliation with Religious Freedom USA, nor with the Cordoba Initiative.

Further P.S.:  To those who plan to participate in the New York march and rally:  If you would like to march with my group (NYARBB) in particular, please RSVP here on our Meetup site.  (There will, I hope, be many other groups participating too, besides NYARBB.)