Snow Hill, in the City of London, was historically the site of one of London's water conduits. Apparently, on special occasions, it was filled with wine.
In his Horatian satire of London, "A Description of a City Shower" (1710), Jonathan Swift references Snow Hill in an accurate description of London's early 1700s drainage system. In his near both Smithfield and St. Sepulchre's, so looking at a map even now you can see how those areas drain to Snow Hill.
Now from all parts the swelling kennels flow,
And bear their trophies with them as they go:
Filth of all hues and odors seem to tell
What street they sailed from, by their sight and smell.
They, as each torrent drives with rapid force,
From Smithfield or St. Pulchre’s shape their course,
And in huge confluence joined at Snow Hill ridge,
Fall from the conduit prone to Holborn Bridge.
Sweepings from butchers’ stalls, dung, guts, and blood,
Drowned puppies, stinking sprats, all drenched in mud,
Dead cats, and turnip tops, come tumbling down the flood. (lines 53-63)