Step 1: Understanding the Concept:
The G20 (Group of Twenty) is an international forum comprising 19 countries and the European Union (and recently the African Union). It works to address major issues related to the global economy. Host cities for the main summit are usually the capital cities of the presiding nation.
Step 2: Detailed Explanation:
1. India's Presidency: India held the G20 Presidency from December 1, 2022, to November 30, 2023. This was the first time the country hosted the summit.
2. The Main Event: While over 200 meetings were held across 60 Indian cities (including Mumbai, Bengaluru, and Hyderabad), the high-level "Heads of State and Government Summit" took place in the capital.
3. Venue Specifics: The summit was held on September 9–10, 2023, at the 'Bharat Mandapam' International Exhibition-Convention Centre located at Pragati Maidan, New Delhi.
4. Key Highlights: The theme was "Vasudhaiva Kutumbakam" (One Earth, One Family, One Future). One of the most significant outcomes was the permanent inclusion of the African Union into the G20.
Step 3: Final Answer:
New Delhi hosted the 18th G20 Summit in 2023.