I am from Russia and will be 20 hr in transit in Beijing. Can we visit city while waiting for flight

Pavel, as you are eligible for the 72-hour free transit policy, you can visit the city wall while waiting for the connecting flight. If you want to book a one-day Beijing tour, you can contact TravelChinaGuide. They will send a tour guide to pick you up at the airport and show you around the city. I used them once and everything was excellent. Email: traveltravelchinaguide.com