Horse-drawn trams were introduced to Edinburgh around 1871.
Trams powered by cable ran from around 1910. The old horse-drawn carriages were sold off for about £6 each.
In the 1920s the city's last cable-operated routes were converted to electric traction.
By the late 1940s the city had one of the most modern tram systems in the UK.
At its peak there were 400 trams in the capital.
The last tram in Edinburgh stopped in November 1956.
The new scheme was approved by MSPs in 2005 and backed by Edinburgh City Council in 2007.
Initial works will mean closure of Shandwick Place for 19 weeks and 16 weeks of disruption on Princes Street from Frederick Street westwards.
It is hoped the first trams will be running around 2010/11.