Bustling Luxembourg City. We enjoy a short guided tour of the bustling capital, followed by plenty of time to see the sights. The City of Luxembourg is not only a historic UNESCO site, with its fortifications lining the steep valley, but also an important European and financial centre with imposing modern buildings. See the Grand Ducal Palace, the Bock and Cathedral of Notre Dame. Relax at a pavement café or restaurant in the pleasant Place d’Armes.