After many decades of service, the old Woolwich Ferries are soon to be decommissioned, and you have just a couple of weeks to take a trip in them.
They are industrial behemoths from a bygone era, plying the narrow stretch of Thames at Woolwich. An upper deck for road vehicles, and vast empty spaces below for the passengers that used to fill the spaces in the days of industrial past and now echo to the rumble of the engines that few come down to hear.
In an era of modern machines, modern fittings and modern engines, these take you back decades to a time when engines growled, seating was hard and the weather cold.
Soon they will be replaced with cleaner, quieter, shinier boats, but the modern will sweep away the heritage.
You have a couple of weeks to ride the past across the Thames, to feel that curious exhilaration as the boat leaves the pier and mighty engines strain to keep a massive ship of steel from being dragged away by the power of the Thames.
The last day is the 5th October, then the Woolwich ferry closes for a few months while the piers are adapted for their replacements.