From publisher blurb: Byzantium. Constantinople. Istanbul, the Sublime Porte... The crossroads between East and West, the center of intrigue in the Middle East. Russian expatriates hide out from the NKVD, Nazis try to gain influence over the government in Ankara, and refugees escaping the spread of communism and fascism are trafficked by forein gangsters under the nose of the Turkish security forces. The Sublime Porte is a sourcebook for adventuring in the Istanbul of the 1930s for the Ubiquity system that powers Hollow Earth Expedition. Covered is the Old City and the European enclave of Pera, as well as the Anatolian side. Two adventure are included, as well as maps for the Grand Bazaar and the Topkapi Palace.