For the most part, the country of Luxembourg is the city of Luxembourg. That is not precisely true, certainly, but the majority of tourist attractions are found within the city limits, actually in the Old Town.
Like Belgium and the Netherlands (see previous posts), Luxembourg is a country that has been overrun by aggressors many times. Much of its legacy is in the form of military fortifications.
Begin an exploration of the city on the Place des Armes, the main square of the Old Town.
Duchy royalty resides at the Palace of the Grand Duke, an elegant structure not far from the main square.
Notre Dame Cathedral is the main church of the Old Town.
Near the Cathedral are fortifications and casemates which are remnants of the World Wars which were fought here.
There are, of course, other squares besides the Place des Armes. One of the most elegant is Market Square..