There is a good reason why it is called tombstoning. Have a go and there is a fair chance you’ll end up with your name on one.
Just ask Graham Dooley. He is 66 now but he has never forgotten what happened decades ago when he was a teenaged apprentice.
A group of his friends were enjoying the summer weather when one dived from a bridge in Weymouth into the harbour.
‘The water was shallow and he broke his neck,’ Mr Dooley tells us today.
‘He later died.’
Mr Dooley spoke to The News after watching a large group of people tombstoning in the Sally Port area of Old Portsmouth.
He was upset. So are we.
For yet again in this column we are forced to plead with young people to stop it.
Stop running and jumping from high objects into the sea.
Stop and think. Do you really know how deep that water is?
Do you know the state of the tides?
Are you certain that an approaching ferry in the narrow harbour mouth is not going to suck you beneath it?
Are there really no hidden obstacles lurking just beneath the surface which could snuff out your life in one neck or back-breaking leap into the unknown?
Councillor Linda Symes, who is in charge of leisure and sport in the city, is on the right lines when she talks about providing an offshore diving platform. Many readers will remember when just such a structure existed here.
But there will always be those adrenalin junkies looking for that extra rush and a chance to show off in front of their mates.
This plea is really aimed at the parents of young children. Put the fear of God about tombstoning into them at a tender age and it might have some impact when they are older.
Or tell them about former soldier Sonny Wells who in 2008 broke his neck after jumping from South Parade Pier, Southsea.
He was 20 and will spend the rest of his life in a wheelchair. And there can be no more eloquent warning than that.