If you are not travelling with a group of fellow tourists, but separately, it is quite expensive to pay for a local tour guide to inform you in detail about the city/cities you are visiting and to give you insights about all the fascination places you are able to see.
The major see sights offer paid audio guides in the main few foreign languages, which can be rented at the ticket desks of the sites, but paying for audio guide at every historical site is also not very ecnomical.
Therefore, we strongly advise you to look up for any available audio guides for the city/cities you are about to visit, as you will most probably be able to find on-line free ( or at least cheap ) audio guides for all main see sights in the major European cities. This way you can have very sufficient and interesting information on the lovely places you visit, and you will have the convenience of using your own smart-phone or mp3-player.
Following the instructions in the audio guides, you will be informed chronologically about the main historical events and development of the sites. You will also be guided through the buildings or areas in a specific order, allowing you to view all essential sights and to hear everything you need to know in order to have a complete and great travelling experience.