A friendship was signed in 1997 with the Russian city Troitsk, together with the partnership of the city Wächtersbach with Troitsk.
From 1986 to 1989 he was a post-graduate researcher at the ETH Zurich (Swiss Federal Institute of Technology), then went on to the Institute of Spectroscopy of the USSR Academy of Sciences in Troitsk near Moscow for half a year.
Troitsk, Moscow, formerly a town in Moscow Oblast, Russia, which was included into the city of Moscow on July 1, 2012
A part of Moscow Oblast's territory, including the towns of Troitsk, Moskovsky, and Shcherbinka, as well as parts of territories of Leninsky, Naro-Fominsky, and Podolsky Districts, has been transferred to Moscow on July 1, 2012.