Some of the numbers surrounding Northland rail:
■ Marsden Pt rail spur - 20km long
■ 30,000 sleepers needed
■ 4 causeways along Oakleigh stretch
■ Realignment of SH1 at Mata
■ North Auckland rail line - 130 years old in places
■ Has to close for safety reasons if not fixed
■ 85,000 extra sleepers needed on the track
■ 13 tunnel floors and approaches to be lowered
■ 7 bridges rebuilt
■ At least $1.4 billion to do both rail lines.
■ Decision due in September or October.

KiwiRail's chief executive Greg Miller has spelled out the work needed to get trains running from Auckland to Marsden Pt.