2001:

Talk of trams begin when it is hoped three routes would crisscross Edinburgh.

2003: Then Transport Minister Iain Gray announces £375m for Edinburgh to build two tram lines .

2004: Costs for lines go up one.

2007: SNP pledge to ditch both the tram scheme and airport rail link. SNP is outvoted. Work on diverting pipes and cables starts.

2008: Construction contract is signed with consortium of Bilfinger Berger, Siemens and CAF.

2009: Bilfinger Berger downs tools, claiming it is owed up to £80m extra payments.

2010: Tie fails to provide updated costs to council. Later that year Tie considers plans to terminate construction contract.

2011: Mediation talks held, work resumes.

2012: Council agrees compensation for firms affected by tramworks.

2013: Trial runs begin.

2014: Prices are unveiled.