How many pence a mile traveling by train?

Depends how far you're going and how much your ticket is...?

depends on the location and zoning for example from where i am to cardiff (wales) is 17.5 miles costs 5.60 return so it works out 0.16 per mile

As others have said, it depends on the journey and ticket you hold.

On London Underground, Covent Garden to Leicester Square is a mere 260 metres (0.16 miles), and cash single is £4.00, which equates to a massive £25.00 per mile!

On National Rail, London Paddington to Heathrow Terminals 1, 2 and 3, for example, is 14.75 miles, and a Standard Class Single is £16.50, which works out to £1.12 per mile, with a First Class Return being £50.00, or £1.69 per mile.

London to Manchester (via Stoke-on-Trent) with Virgin Trains is 184.25 miles, and ranges from £11.00 for the cheapest Standard Class Single (6p per mile) to £387.00 for the most expensive First Class Return (£1.05 per mile).

Another example is Ryde Pier Head to Ryde Esplanade on the Isle of Wight, a distance of 0.25 miles. A Single ticket is 90p (£3.60 per mile) and a Return is £1.40 (£2.80 per mile).

A similarly silly example is Silver Street to Edmonton Green, a distance of 0.5 miles. As a result of the Zonal pricing scheme in London, this is £1.70 Single (£3.40 per mile) and £2.90 Return (£2.90 per mile).