Toompea Castle, with a view of the Tarim. The whole Upper Town, also known as the Church Hill, is named for the Notre Dame Mary Cathedral. The area where the Church is located, besides government agencies, foreign embassies, official residences, there are several viewing terraces, which can enjoy the whole city of Tallinn and the port of Tallinn. To appreciate the scenery of Tallinn, you must come to the viewing platform located in the four corners of Zhetang Mountain, where you can not only enjoy the Old Town of Tallinn, but also see Helsinki, Finland, across the Baltic Sea in good weather.