Remnants of the "monster fatberg" discovered in a London sewer in September 2017 are on display at the Museum of London.
The 130-tonne, 250-metre-long Whitechapel fatberg was choking a central city sewer and took more than two months to remove.
A Thames Water spokesman said the toxic mass of sewage, fat, grease and rubbish grew over a period of several months between sewer inspections.
Workers used high-powered jets, shovels and smaller hand tools to break it up, Fatberg curator Vyki Sparkes said.
"The samples we have [on display] reflect that process," Ms Sparkes said.
The still-hazardous remnants were air-dried, then locked inside specially sealed units for the temporary exhibition.
Ms Sparkes said while fatbergs were usually destroyed, the museum wanted to preserve a symbol of contemporary history.
"They are the only remaining parts of the Whitechapel fatberg and also it's the first time that any museum ever has put fatbergs on display. It really is a world-first," she said.
"It reflects a real concern facing Londoners today and for us it was really important that we reflect these issues."
Thames Water education manager Liz Banks said fatbergs were fed by grease and oils, so-called "disposable" wet wipes and a multitude of things not meant for the sink or toilet.
Thames Water — the UK's largest water and wastewater services company — clears one sewer blockage more than every seven-and-a-half minutes and spends about $1.8 million each month clearing blockages from the sewer network.
"Some people might consider a toilet like a bin. In fact, we prefer that people put them in the bin and we say 'bin it; don't block it'," Ms Banks said.
She said most of the monster fatberg was melted and converted to biofuel that could be used to power vehicles such as London's buses.
The exhibition might not be to everyone's taste, but it was hoped the publicity would encourage people around the world to consider what they poured down the sink.