Yes, it’s possible to visit both in one day, but strict timing and advance bookings are essential: The Forbidden City: Requires reservations 7 days in advance via the official website/app. Entry is time-slotted (morning/afternoon), and tickets sell out quickly, especially in peak seasons (March–November). Tiananmen Square: Needs to be booked 9 days in advance through the "Tiananmen Square Visit Reservation" WeChat mini-program. No time slots, but security checks are strict—arrive early with your passport. Suggested Itinerary for Same-Day Visit: Morning: Start at Tiananmen Square (open 24/7, but security lines are shorter before 8:00 AM). Visit the Monument to the People’s Heroes and Tiananmen Rostrum (if open). Late Morning: Enter the Forbidden City via the Meridian Gate, using your pre-booked ticket and passport. Allow 4–5 hours for the tour, exiting through the Shenwu Gate to Jingshan Park for panoramic views. Afternoon/Evening: Optional add-ons: Climb Jingshan Park, visit the Palace Museum (extra tickets), or walk to nearby Qianmen Street for dinner. Tip: Both sites enforce strict ID checks—carry your passport at all times, and avoid bringing large bags to speed up security.