Although Georgians are very religious, gluttony is not a sin here. Tbilisi is all about food: seducing aromas – of juicy kebabs, freshly baked flatbread, hearty lamb stews – will start chasing you right after you enter this sunlit ancient city. And it doesn't really matter if it is the posh, lush Rustaveli Avenue or shabby little streets of the historical neighbourhood Sololaki – every joint selling the Georgian masterpieces hinkali or hachapuri is worth stopping by. Even if you have just had lunch. And don't forget the wine. Local heavy, rich red is a legend all around ex-Soviet Union countries and will be your perfect companion in sightseeing – and life per se.
Famous thermal baths are not the only place for sulphur-rich thermal water – it runs out of tap at some old city flats, too!
At the end of the day, promise yourself a funicular ride up to the National Botanical Garden. The view will likely make your heart stop. A little while.