Question: What is the address where the Peace Conference of 1861 was held?

Context paragraphs:
Christian Peace Conference: The Christian Peace Conference was an international organization based in Prague and founded in 1958 by Josef Hromádka, a pastor who had spent the war years in the United States, moving back to Czechoslovakia when the war ended.  Hromádka was a member of the Bureau of the World Peace Council.  He was not a Marxist, but the Christian Peace Conference often endorsed positions taken by Eastern bloc governments.  It has been alleged to have received $210,000 from Soviet sources.

Peace Conference of 1861: The Peace Conference of 1861 was a meeting of 131 leading American politicians in February 1861, at the Willard's Hotel in Washington, DC, on the eve of the American Civil War.  The success of President Abraham Lincoln and the Republican Party in the 1860 presidential elections led to a flurry of political activity.  In much of the South, elections were held to select delegates to special conventions to consider secession from the Union.  In Congress, efforts were made in both the House of Representatives and the Senate to reach compromise over the issues relating to slavery that were dividing the nation.  The conference was the final effort by the individual states to resolve the crisis.  With the seven states of the Cotton South already committed to secession, the emphasis to preserve the Union peacefully focused on the eight slaveholding states representing the Upper and Border South, with the states of Virginia and Kentucky playing key roles.

Willard InterContinental Washington: The Willard InterContinental Washington is a historic luxury Beaux-Arts hotel located at 1401 Pennsylvania Avenue NW in Washington, D.C. Among its facilities are numerous luxurious guest rooms, several restaurants, the famed Round Robin Bar, the Peacock Alley series of luxury shops, and voluminous function rooms.  Owned by InterContinental Hotels & Resorts, it is two blocks east of the White House, and two blocks west of the Metro Center station of the Washington Metro.

A Peace Conference at the Quai d'Orsay: A Peace Conference at the Quai d'Orsay is an oil-on-canvas painting by Irish artist William Orpen, completed in 1919.  It was one the paintings commissioned from Orpen to commemorate the Paris Peace Conference in 1919.  The work is held by the Imperial War Museum in London.

Geneva II Conference on Syria: The Geneva II Conference on Syria (also called Geneva II Middle East peace conference or simply Geneva II) was a United Nations-backed international peace conference on the future of Syria with the aim of ending the Syrian Civil War, by bringing together the Syrian government and the Syrian opposition to discuss the clear steps towards a transitional government for Syria with full executive powers.  The conference took place on 22 January 2014 in Montreux, on 23–31 January 2014 in Geneva (Switzerland), and again on 10–15 February 2014.

Paris Peace Conference, 1919: The Paris Peace Conference, also known as Versailles Peace Conference, was the meeting of the Allied victors, following the end of World War I to set the peace terms for the defeated Central Powers diplomats from more than 32 countries and nationalities.

Annapolis Conference: The Annapolis Conference was a Middle East peace conference held on 27 November 2007, at the United States Naval Academy in Annapolis, Maryland, United States.  The conference aimed to revive the Israeli–Palestinian peace process and implement the ""Roadmap for peace"".  The conference ended with the issuing of a joint statement from all parties.  After the Annapolis Conference, the negotiations were continued.

Czech Corridor: The Czech Corridor was a failed proposal during the Paris Peace Conference of 1919 in the aftermath of World War I.  The proposal would have carved out an area of land to connect the Kingdom of Yugoslavia and Czechoslovakia.  A different name often given is "Czech–Yugoslav Territorial Corridor".  It is called the Czech Corridor, because representatives of Yugoslavia at the Peace Conference stated that they would prefer it be given to the Czechs.  The proposal was rejected by the conference.

Eastern Committee: The Eastern Committee (1918–1919) was an interdepartmental committee of the War Cabinet of the British Government created towards the end of World War I.  It's creation was approved by the War Cabinet on 13 March 1918 and it held the first of 49 meetings on 28 march 1918, and having prepared British desiderata for the Paris Peace Conference of 1919 dissolved itself on 7 January 1919.  It was in turn replaced by the ad-hoc Interdepartmental Committee for Middle Eastern Affairs, Lord Curzon of Kedleston(Lord President of the Council) still in the chair while deputizing for Secretary of State for Foreign Affairs Arthur Balfour in his absence at the Peace Conference.

Madrid peace conference letter of invitation: The Madrid peace conference letter of invitation, also known as the Madrid Invitation or Letter of invitation to the Middle East Peace Conference in Madrid, of October 19, 1991, was a formal diplomatic invitation by the United States and the Soviet Union issued to Israel, Syria, Lebanon, Jordan and the Palestinians, calling on them to come together and hold a peace conference in Madrid, Spain.  The resulting conference came to be known as the Madrid Conference that commenced on October 30, 1991.

Supporting paragraphs: Peace Conference of 1861 Willard InterContinental Washington
Answer: 1401 Pennsylvania Avenue NW