Stations to span the Severn Estuary are planned at the Grand Pier and Cardiff’s Mermaid Quay.
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Similar to the cable cars of San Francisco, the proposed monorail would be both transportation and a tourist attraction. Using electric power, however, would be problematic due to the corrosive nature of salt water in the Severn Estuary. Each train's motor therefore would run by compressed natural gas, an eco-friendly energy source.
Sloan