RETZKO studied civil engineering at the Hannover University of Technology until 1955. From 1955 to 1961 he served as a scientific assistant at the Institute of Traffic and Transport Economy, Highway Engineering and Urban Planning at that university. In 1961, he received his doctoral degree. In the early sixties, RETZKO was traffic and transport engineer in the town planning office of the City of Nürnberg. His fields of activities were planning, design and operation of urban traffic and transport facilities, especially streets, motorways, parking and public transport; traffic signal settings; accidents research. Thereafter he became an official in the department of the Federal State of Lower Saxony, Hannover. Here he served as expert for civil engineering in urban planning and was responsible for all civil engineering projects in the cities and towns of Lower Saxony. Since 1966, RETZKO has been professor for traffic and transport engineering at the Darmstadt University of Technology, where he has been researching and teaching especially on traffic and transport planning methods, on traffic and transport theories, and on planning, design and operation of traffic and transport facilities. He served three times as Dean of the Faculty of Civil Engineering, and he was a member or/and chairman of many committees of the university.
RETZKO is member of many national and international organizations. He became Member of Honour of the Hungarian Association for Traffic and Transport Science. He made congress, study and lecturing tours to European countries, and to Argentina (1980), Canada (1981), China (1985, 1995, 1999, 2004, 2005, 2006 twice, 2007), Colombia (1980), Hong Kong (1992), Israel (1978, 1989, 1991, 1994, 1997), Japan (1967, 1970, 1972, 1977, 1990, 1993, 1994, 1999), Korea (1992), Mexico (1975, 1980), USA (1969, 1976, 1987, 1993) and Vietnam (1998, 2000, 2001, 2002, 2004 twice, 2005).
He participated in many national and international congresses (sometimes as general reporter and as national reporter).
RETZKO published 206 technical papers and books.
Outside his university, RETZKO is consulting federal and state ministries, regional authorities, cities and other public or private institutions. He established many projects, especially on urban traffic and transport planning.
RETZKO received several honours: in 1973 a gold medal by the Hungarian Association for Traffic and Transport Science (“Abzeichen mit dem goldenen Kranz”), in 1984 the Honorary Membership of this association, in 1995 a merit medal of his university (“Erasmus-Kittler-Medaille”), in 1996 the Honorary Doctor Degree by the Dresden University of Technology, in 2002 the German First Class Merit Medal (“Verdienstkreuz 1. Klasse des Verdienstordens der Bundesrepublik Deutschland”), in 2003 the “Medal for Merits in Educational Matters” by the Sozialistic Republic of Vietnam and in 2006 the title of “Advisory Professor” by Tongji University Shanghai, China.
Darmstadt, June 2007