Adelaide of Vianden, German countess

Countess Adelaide of Vianden was a countess from the House of Vianden, the cadet branch of the House of Sponheim that ruled the County of Vianden, and through marriage Countess of Nassau-Siegen. She acted as regent of the County of Nassau-Siegen for her eldest son in the period 1351–1362.

September 30 is the 273rd day of the year in the Gregorian calendar; 92 days remain until the end of the year.