Where was the United Nations Charter signed by 51 original members of the United Nations?

The United Nations Charter was signed at the United Nations Conference on International Organization, commonly known as the San Francisco Conference [1][6]. The conference took place in San Francisco, California, from April 25 to June 26, 1945 [1][7]. Delegates from 50 nations initially met to draft and agree upon the Charter based on proposals from Dumbarton Oaks and the Yalta Agreement [1]. On June 26, 1945, the Charter was signed by 50 nations [1][3]. Poland, which was not represented at the conference, signed the Charter later on October 15, 1945, bringing the total number of original founding members to 51 [1][3][5]. The Charter officially entered into force on October 24, 1945, after ratification by the five permanent members of the Security Council and a majority of other signatories [4][6].

Sources

1. [1] Contemporary World Politics, Textbook in political science for Class XII (NCERT 2025 ed.) > Chapter 4: International Organisations > FOUNDING OF THE UNITED NATIONS > p. 48
2. [6] https://treaties.un.org/doc/publication/ctc/uncharter.pdf
3. [7] https://media.un.org/photo/en/asset/oun7/oun7757364
4. [3] https://1997-2001.state.gov/background_notes/un_0007_bgn.html
5. [5] https://www.congress.gov/crs-product/R48306
6. [4] https://research.un.org/en/unmembers/founders