Passage: The OPEC Fund for International Development (OFID) is the intergovernmental development finance institution established in 1976 by the Member States of the Organization of the Petroleum Exporting Countries (OPEC).  OFID was conceived at the Conference of the Sovereigns and Heads of State of OPEC Member Countries, which was held in Algiers, Algeria, in March 1975. A Solemn Declaration of the Conference "reaffirmed the natural solidarity which unites OPEC countries with other developing countries in their struggle to overcome underdevelopment", and called for measures to strengthen cooperation between these countries.OFID's objective is to reinforce financial cooperation between OPEC Member Countries and other developing countries, by providing financial support to the latter for their socioeconomic development. The institution's central mission is to foster South-South Partnership with fellow developing countries worldwide with the aim of eradicating poverty. OFID's headquarters are located in Vienna, Austria. The current Director-General is Dr Abdulhamid Alkhalifa of Saudi Arabia. He assumed office as Director-General and Chief Executive Officer of OFID on November 1, 2018.

Question: Where are OFID's headquaters located?
Vienna, Austria