'˜Ring of steel' amid high security for Harry and Meghan's wedding

Prince Harry and Meghan Markle's post-wedding carriage ride route may be closed to latecomers if the 100,000 revellers expected become a safety issue.

Details of Thames Valley Police’s operation to safeguard the newlyweds, their guests and spectators have been released, with airport-style security scanners and bag searches also planned in Windsor.

Metal barriers will be erected in the Berkshire town to deter attackers from using vehicles, like the terrorist atrocities committed on London and Westminster bridges.

Tight security planned for Prince Harry and Meghan Markle's wedding. Pic: AFP/Getty Images

The measures will effectively create a ring of steel around Windsor Castle’s St George’s Chapel where the couple will exchange vows.

The May 19 wedding is one of the largest public events policed by the force and in the run-up more police will be seen on patrol in the town, from armed officers to those with dogs and even mounted police on duty.

With the US actress a big draw both to British and American fans, huge crowds are expected, with the processional route of the carriage ride estimated to hold around 100,000 spectators.

If the number of visitors proves to be a safety issue, Thames Valley Police, in consultation with others like Network Rail and British Transport Police, could order trains not to stop at Windsor’s two stations and close off the route to latecomers.