If your trip to Cardiff is all organized but your travel itinerary is a little on the empty side, let us give you a few hints and tips.Explore the best that this place has to offer by adding Principality Stadium and Cardiff Castle to your travel schedule. If you've got some spare time, take a look at National Museum Cardiff and Wales Millennium Centre too.Not far from the heart of the city, Cardiff Bay is one spot you might like to consider adding to your must-see list. Cardiff City Stadium and St. David's Hall are also close by and worth checking out.