Alarge yellow sign stood in the middle of a patch of grass that may have had hopes of being called a lawn if it ever grew up and emigrated to England. The sign had the words "In case of steaming, ring 488-9488." Underneath is written "5 m" with arrows pointing to the left and right.

Those first four words were enough to make me stop and decide never to cross that piece of fading green even if being chased by all the stray dogs in Moscow.

The sign was a warning of what was bubbling underneath. And it brought back memories of a horrific story 10 years ago.

Moscow's network of pipes delivers hot steam and water to buildings all over the city -- the heating was turned on recently, and it should be cozy in your flats this week, just in time for the heat wave this weekend -- and are often the most visible invisible sights in the city.



You think it would be hard not to see the huge pipe the size of a mountain that climbs into the sky on 1st Ulitsa Yamskovo Polya near Belorussky Station, creating a bridge over the road, but for some reason it took me years to notice it.

Other pipes are around town wrapped in fluffy, torn lagging, like a down on her luck night butterfly, making its way down the streets or around apartment blocks.

And then there are the miles of pipes underground, under everyone's feet and invisible unless you have Superman X-ray vision. They are cased in special boxing but the sign "in case of steaming" shows that sometimes something can go wrong.

It was 1998 when this paper wrote of how a 9-year-old boy cut across a lawn and disappeared after a hot water pipe that was just under the grass burst, turning it into a steaming swamp. His father jumped in to pull him out, and the pair suffered severe burns.

That burst pipe was somewhere near Timiryazevskaya metro station. Witnesses said they had spotted steam coming from the ground a few hours before the accident and that local authorities had been told, but no one turned up before the accident.

Officials could not explain at the time how the water and steam had gotten past the box that surrounds the pipe. It was also a time when cars would fall into craters that opened up in roads, but I remember this was something particularly shocking. Perhaps the signs were added after the incident.

Nobody answered at the 488 number when I rang Thursday. Luckily, there was no sign of steaming either.