Arrival in Beijing

I will be having meeting in Shanghai and to obtain China visa I submitted documents in Chinese Consulate General in Karachi, Pakistan with Original Invitation Letter attested by the Ministry with red seal from Shanghai. I want to arrive in Beijing and would like to go to Shanghai through train. Please note that I submitted all documents showing my stay in Shanghai. Can I presume that having valid visa of China means we can arrive in any city of China. I will be departure from Shanghai airport. Please reply and guide me.