Make boresome and expensive excursions unnecessary.
Series of audio guide mobile apps for various world capitals, as Athens, Riga, Vilnius are a good alternative for those, who hates organized excursions but finds pocketbook tourist information not enough. Any of the 3 apps has a map and a catalogue with the major city landmarks marked.
Map with all main attractions. Every site is provided with a profound historic comment in two forms: text and audiotrack.