The Louvre museum in Paris has multiple entry points. The glass pyramid is the most popular entry point, often inundated with long lines. If you have the Paris museum pass (good for multiple museums in Paris), you could move to the beginning of the line and then go through the security checkpoint.
The lines are much shorter in the afternoons especially on days when the Louvre museum is open late (Wednesday and Friday). Waiting on line, there are signs informing the visitors to be beware of pickpockets. That surely bring the euphoria of being in a beautiful city down a couple of notches.
I myself still am in awe of the sheer vastness of this place and the treasures it hold despite several visits before. On the most recent trip, I finally get to see the "Venus de Milo" statue - an image that I have seen as a child not knowing what it meant except that the lady was armless. Seeing it in person, it is a marvel that this Greek classic statue was sculptured so perfectly and remained very well preserved over the centuries.
The Louvre museum has a huge sculpture gallery with wide expanse of marble figures. One would really need days to explore this museum so it is best to take in the Louvre's treasures in small appreciative doses.
The Louvre, a former palace, with its pyramid and surroundings are illuminated at night. The glow of the lights cast a really magical spectacle. On the palace grounds, one could also see the Eiffel Tower glowing and sparkling at the top of the hour.
Paris is definitely breathtaking at night !