My macro:
stand on beginning of Leicester
start recording
shift-end
ctrl-c
end
space
delete
end
space
delete
home
down arrow
ctrl-v
end
enter
up arrow
stop recording
replay recording
replay recording
replay recording
replay recording
replay recording
…
end up with extra Leicester to delete.
A simpler approach would be to just merge every 2 lines and then add the common prefix with column editing.