Luxembourg in December

May through October gives you the best weather and longest days. Summer temperatures hover around 20-25°C (68-77°F) — perfect for castle hopping and riverside walks. July and August bring crowds to popular spots like Vianden Castle, but Luxembourg never feels overwhelming like other European destinations. Spring (April-May) offers blooming countryside and fewer tourists, though some outdoor attractions have limited hours. Fall colors in the Ardennes region peak in early October, making it ideal for hiking the Mullerthal Trail. Winter has its charm — Christmas markets fill Place d'Armes from late November, and indoor attractions like the National Museum stay cozy. But many castle tours reduce schedules and some countryside restaurants close entirely. The shoulder seasons of late April and September offer the best balance of good weather and reasonable prices. Avoid the first week of August when half of Europe seems to vacation here simultaneously.