Three Mills is an historic milling, distillery and industrial site on the Lower Lea, technically in Newham but with more links historically to Bromley by Bow in Tower Hamlets.
It’s been the site of various tide and wind mills and distilleries since the 11thC and in the 1776, Grade I listed building House Mill, has the world’s largest surviving tidal mill.
The House Mill website states ” The mills provided flour for the local bakers of Stratford-atte-Bow who sold their bread in the City of London. A rare exception is recorded in 1588, the year of the Spanish Armada, when a gunpowder mill contributed to England’s war effort against Spain. With the advent of the Gin Craze in the 18th century, several entrepreneurs came together to put the mills to an altogether different use – as part of the Three Mills Distillery. … In 1776 the House Mill was built on the site of an earlier mill and between two houses, hence its name. The iconic Clock Mill, opposite, was rebuilt in 1817. There was also a third mill, a windmill, which survived until about 1840. In the early 19th century the distillery was owned by the Tory MP Philip Metcalfe, before its acquisition by J&W Nicholson & Co in 1872 which produced the once popular Lamplighter Gin and established a network of freehouses, many of which continue today.”   
Wikipedia notes House Mill was damaged by fire in 1802, and rebuilt. 
The paving is exceptional with it’s mix of massive granite blocks cartway or stoneway and granite setts. And as I noted at the Filter Beds, 3 miles and an hours’s walk according to Google, up the Lea Navigation, these are also a lovely mix of colourful granites, with probably some red Aberdeenshire, maybe pink Mountsorrel and some black basalt. And all in perfect weather! If your ever want to take photos of granite wait for some light rain!
It is possible this is the longest existing cartway or stoneway in London. I know of other short ones in Southwark, by Smithfields, in Islington and Hampstead but these are just in alleyways. An article in the Greater London Industrial History Society newsletter in December 1981 has the Three Mills ‘stoneway’ is it’s longest stoneway example. 
I mentioned cart wheel tracks tracks in my previous post on Albury and Lamerton Streets in Deptford and even though there is a clear granite block cart road, it’s clear the carts did not always keep to it! 😀 
Pleased to see English Heritage have given a specific listing to this paving although they don’t go into much detail!
” C19. Paving of stone setts with flagstones marking pathway across from the Clock Mill to the House Mill. Important in the Group scene.” 
In terms of dating based on the rough cut of the setts and that there were major works done in 1817 if I was to put a wager on it would be for that date.  It’s also possible they date from when it became a distillery in 1872. Mountsorrel granite was being supplied to London in the early 19thC by granite so the earlier date is possible. 
Three Mills is well worth a visit and there’s lots of walks up and down the Lea Navigation and the Bow Back Rivers, and although the whole area has changed massively in the last 20 years with redevelopment there’s still plenty of interesting things to see.  
But wait till my (next) post on Three Mile Island Green! 😉
Getting There :
Very easy to walk, cycle or get there by public transport
By London Underground & DLR – The nearest station is Bromley-by-Bow, which is served by the Hammersmith & City and District lines and is a 10 minute walk away.
The nearest DLR stations are Abbey Road, Bow Church, Devons Road, Pudding Mill Lane and Stratford High Street, and are all a 15 minute walk away
By Bus – Bus routes 108. D8 and 488 stop outside Tesco, Three Mill Lane – a 3-minute walk away and the 25, 276 and 425 stop at Stratford High Street Bow Flyover – a 5-minute walk away
 The Rock Quarries of Charnwood Forest Annette McGrath http://www.emgs.org.uk/files/mercian_vol13on/Mercian%20Geologist%20volume%2016%202004-2007/Mercian%202007%20v16%20p241%20Chranwood%20quarries,%20McGrath.pdf