What happens if you cross the Severn Bridge but have no cash

[Horsepower27]

Drove over the (New) Severn Bridge yesterday and paid my toll, in cash. Rip off!! Was the first time for 10 years I've been over there and made me think of something.

There are signs before the bridge saying cash only and NO CARDS and they are a few junctions in advance so in theory you turn off and try and find a cashpoint but what happens if you mistakenly think you do have enough cash but when you turn up at the toll you find you don't?!

It's not like you can turn around and go back again?!!

[Horsepower27]

Why are they still charging tolls? I know it must cost quite a bit to maintain but surely it's been paid for by now?!

Good idea about the toll +50p for paying by card. Agreed, I don't think that's unreasonable