1. Union Square is a public park located in the heart of New York City, specifically in the Manhattan district. The park was named after the pro-Union rallies that took place there during the American Civil War. It covers an area of 3.6 acres and is surrounded by different art galleries, retail stores, and restaurants. Union Square has a long-standing reputation for attracting protests and public events, including rallies, concerts, and gatherings.

2. Union Square Park opens daily at 6 am and closes at 1 am. You can contact them at +1 212-971-0630 for more details.

3. Union Square is easily accessible via public transportation. Subway lines N, Q, R, W, L, 4, 5, and 6 all stop at the Union Square Station. There are also multiple bus routes that stop near Union Square. The park does not have an entry fee, and admission is free for all visitors.