1. Senate Square (Senatskaya Ploshchad) is a historic square located in the heart of St Petersburg, Russia. It was designed by the famous Italian architect Carlo Rossi in the early 19th century and is considered to be one of the most beautiful and majestic squares in Russia. The square is dominated by the impressive building of the Senate and Synod, which was the highest legislative and judicial body in the Russian Empire. The other notable buildings on the square include the famous bronze statue of Peter the Great, the Cathedral of Saint Isaac (nowadays a museum), and the Mariinsky Palace, which houses the headquarters of the St Petersburg administration. The square also has a beautiful fountain decorated with statues and a picturesque garden where locals and tourists can relax and enjoy the city views.

2. The working time of Senate Square is 24/7, as it is a public area. There is no phone number for the square itself, but you can contact the tourist information center of St Petersburg at +7 (812) 310-2104 for more information.

3. There is no ticket or admission fee for visiting Senate Square. The square is easily accessible by public transportation, including buses, trolleybuses, and metro. The closest metro station is Admiralteyskaya, which is located within a 5-minute walk from the square.