The Worshipful Company of Woolmen will be hosting their annual sheep drive across the river to re-enact a Freeman's ancient right of taking his sheep into town without paying a toll.
They will be accompanied by the Lord Mayor of London and a special celebrity guest (last year's was the Hollywood actor Damien Lewis).
The bridge will be completely closed to traffic for the day so the public can watch groups of sheep be herded across at 7-minute intervals between 10 AM and 4 PM.
History of the Sheep Drive
The tradition dates all the way back to medieval times when London Bridge was the only way for farmers to get their sheep to market to sell their meat and wool. The City's Freemen were excused the usual crossing toll in recognition of their status as local traders.
The invention of motorised vehicles in the early 20th-century eventually put paid to the practice, but the tradition was given a welcome revival in 2013 and has now become an annual affair on either London Bridge or Southwark Bridge (this year it's Southwark Bridge), invoking the memory of London life in years gone by.
Livery Fair & Sheep shearing demonstration
Livery companies will also be setting up stalls around the area of The Monument to demonstrate their trades with colourful displays about textiles, arts and crafts.
You'll also be able to watch the Livery members showcase skills like basket-making, wood-turning and sheep shearing, visit a pen containing some rare sheep breeds, and buy some of their wool-based products in the surrounding stalls.