Where were the crossing points on the Severn River in the 1860's?

The lowest road bridge across the Severn was Telford's crossing at Over/ Gloucester.

There were numerous ferry crossings around the great horse shoe bend between Whitminster/Arlingham -> Newnham

The railway had a steamer crossing between Sudbrook, Mon and Old Passage ( approx).

There was a coastal trade between Bristol and Newport / Chepstow but I guess this is technically the Bristol Channel :-)

< The Severn Rail bridge near Lydney was built around the mid 1870's >