I always find that if you are in a city for a very short time, then going on the City Bus Tour (which many main cities have) is one
excellent way to see a lot in a short time and which a guide. The best ones I find are the hop on, hop off bus tours. An organised city tour can also be a great way and if the city has a river through the heart of it, as Prague has, a boat trip combined with city tour can be good.In Prague, companies who offer good tour include Viatour and GoldenTours. They are several companies in fact that you can choose from and often the tours use the same supplier. If you are unsure, then talking to your hotel concierge or to your Prague apartment agent can also sometimes help.