We visited Luxembourg as a day trip from Trier, driving around the scenic vineyards in the southeast of the country and spending an afternoon in the capital city. The city is built on a series of plateaus divided by the Petrusse and Alzette rivers. This is part of the Petrusse gorge as seen from the city center.
The most excitement you can have in Luxembourg City is probably trying to park a car in the city center, especially on a business day. That's not to say there is nothing to do here. Tour groups for instance seem to particularly congregate around Notre Dame Cathedral. Luxembourg is considered one of the most expensive cities in the world to live in (and eat in too!). The central district is very lively during the day although it seemed like most of the hotels were outside the central plateau.
The center of Luxembourg City is, or has been, completely fortified at various times in its history. Along the Petrusse there are massive stone walls. Down in the gorge is now a very nice system of parkland with trails winding along the river. Unfortunately, after you go down there and wander around a bit, you have to climb back out of it.
On the right side of this picture is the Palace of the Grand Dukes of Luxembourg. It's not very ostentatious as palaces go and it's just right in the middle of the city. On the left side of the picture are a series of very over-priced restaurants.
The Alzette side of the plateau is also heavily fortified and is laced with catacombs as well. The series of tall buildings in the distance are across the Alzette bridges on the plateau called the Kirchberg. This is mostly comprised of EU government buildings, convention centers and massive hotels.
We came across this flower market in one of the squares of Luxembourg City. There was also a farmers' market of sorts and we actually ended up eating here. We're not sure if there is some sort of typical Luxembourgish dish or not. We couldn't find anything like that if there is one. Most of the food was a mix of French, German and Dutch cuisine as one might expect. So we had an assortment of fruit (plums were definitely in season), cheese and olives before returning to Trier.