Approximately 215 miles - and would take roughly 3 hours 45 minutes by road.
The distance between Sherborne ferry port and Dover ferry port is 194 miles. The travel time by car is 3 hours and 20 minutes.
120 miles
Holyhead, Isle Of Anglesey to Gosport, Hampshire = 331.1 miles.
You can't take a ferry from London to Caen. The nearest UK port for Caen (Ouisterham) is Portsmouth in Hampshire.
About 85 miles.
its 160 miles probally
115 miles taking this route:Take A55 BANGOR, from Holyhead, to M56 MANCHESTER at J34.Take M56 to MANCHESTER.
31 miles. 18 miles drive to Port Clinton, 13 mile ferry ride.
161 miles by road. See the link below.
The main ferry port linking Ireland and Britain is Fishguard, which is in Wales. It is not far from England, so it is the one people would use.
Actual distance will depend on which road you choose to use, but using the line measure tool on Google Earth, Holyhead is about 218 miles (351 kilometers) northwest of Heathrow Airport.
As far as I can find out the First USS fulton,(Demologos) had a copper boiler located in the port side hull. The boiler was 22' long by 14' dia.