There is almost always something going on in Luxembourg City, be it a regular weekly event or a more celebrated annual festival. For instance, every Wednesday and Sunday are market days, when place Guillaume is overtaken by stalls selling everything from fresh fruits, vegetables and beautiful flowers to spices, goat cheese, and homemade jam. Definitely come to look, and feel free to politely haggle if you feel an urge to buy. And on countless Sundays from June through October there are open-air band concerts at the place d’Armes. The Grand Ducal Big Band for Military Music and other bands from the surrounding towns take turns entertaining the crowds with everything from classical music to show tunes.

During Lent there are several festive street carnivals, winding up with a more serious celebration, Oktave of Our Lady of Luxembourg, a pilgrimage to honor the patron saint that lasts from the third to the fifth Sunday after Easter. An other celebration we could find is the "Spring" or Dancing Procession of Echternach, held on Tuesday after Whitsun in honour of St. Willibrord (see more: http://www.luxembourg.co.uk/dancproc....

June 23 is National Day, when spectators get to watch the Grand Duke review his troops. The day before, on June 22, People party starts on evening in the streets, following by a local folklore train and then gather to watch the fireworks display at night over the Petrusse Valley.

And late August brings Schueberfouer, a large traveling fair, to the huge Glacis Square. Founded in 1340 by John the Blind, Count of Luxembourg and King of Bohemia, it continues the tradition of the folk fair. 

Here some informations for Festivals: International Festival of Classic music in Echternach (June); International Theatre and Music Festival in Wiltz (July-August); Medieval Festival in Vianden (1st W-E in August); Summer in the City and Streeta(rt)nimation (June-September); Rock um Knuddler and Blues'n Jazz Rallye (Luxembourg-City on July); Journée Européenne du Patrimoine (3rd Sunday of September); The Nights of the Museum (October)