I don’t think there is an accurate translation for the expression walking distance.
Raggiungibile a piedi probably works, but it is not exactly the same thing.
The Italian concept of walking distance is very different from the american one. 1 km is definitely walking distance in Italy, a couple of blocks is probably long enough to take a cab in the States.
In Italy walking is natural, and very often much easier than drive.
Former President Pertini (Sandro Pertini, 1896-1990, http://en.wikipedia.org/wiki/Sandro_Pertini probably the most popular president ever and the most loved by generally-not-very-patriotic-Italians) used to walk to work every morning, chatting with random people he met on his way.
Many Italian towns, built in the Middle Ages or maybe even at the time of the Roman Empire, are not designed for driving (streets are often too narrow, no parking lots…). So you just walk. On the same roads that generations of Italians walked before you.