The
constructing of roads and bridges, the building of rest-houses
and the making of provisions for travellers has always
been an important and popular expression of Buddhist generosity.
The reasons for this are not clear. Perhaps it is because
the Buddhist life is seen as analogous to a journey, samsara
to raging river that has to be crossed and Dhamma to a
means of crossing. The first exhortation to aid the traveller's
way is to be found in the Pali Tipitaka.
In the Anguttana Nikaya, the Buddha says that those who
build causeways and bridges will make much merit for themselves.
King Asoka took this as a cue to
have roads straightened and repaired, to have them lined
with trees and to have wells dug at regular intervals
along them.

Numerous
records from the Buddhist period in India
mention similar good works. A 15 century Tibetan saint
built an iron chain suspension bridge that was still in
use in the 1950's. In medieval Japan building roads and
bridges as an act of piety became almost an obsession.
Monks and nuns were forever touring the country collecting funds
for such projects and usually the whole community participated
in the actual construction. A document dated 1276 concerning
the construction of a bridge over the Midori River says:
"People of high and low estate crowd on either bank,
bickering constantly. People and horses vied to board
small boats that then capsize, drowning their passengers".
The monk who built his bridge says he did so because :
" When we see a dangerous situation, we must make
it safe, for the Buddha has compassion for people".
Before the rise of the modern states with public works
departments, the Buddhist enthusiasm for building roads
and bridges had a significant role to play in developing
trade, communications, the spread of ideas and generally
lessening of the hardships of life.