The Russian (often mistaken for Greek) Orthodox Church on the Neroberg Park in Wiesbaden.

This was built between 1848-1855 as a tomb and chapel for Elizabeth Michailovna, Duchess of Nassau and Grand Duchess of Russia, niece of the Russian Tsars
Alexander I and Nicholas I. Barely a year after her marriage with the pious Duke Adolf of Nassau she died at childbirth - along with her newborn child.