At Euston fire station drivers in lorries, cars and taxis sounded their horns in support of the firefighters. The union's own fire engine was driven onto the station forecourt, with Johnny Cash's Ring of Fire song blaring from a loudspeaker:
We have been receiving a lot of public support today at picket lines across London.
There is solid support for the strike - but it is a sad day in some respects because firefighters don't want to be on strike.
More top news
Made In Chelsea star Mark-Francis Vandelli has become the fourth celebrity to withdraw from the winter sports programme.
Just off Fleet Street stands a famous tiered tower. Designed by Sir Christopher Wren, it became the inspiration for the wedding cake.
The president of the respected Royal Institute of British Architects became the latest high profile figure to enter the row.