Anchor Road, Canons Road, Canons Way, Lower College Street, Bridge Valley Road, the Portway, some roads around the Cumberland Basin System and others will be closed early morning until mid-afternoon.
The race starts at 09:30 from Anchor Road, Harbourside.
More top news
A tower in Bristol's Cabot Circus has cladding in the same category as the cladding that was on Grenfell Tower.
A partial solar eclipse can pose more risk to eyesight than a full one, scientists have warned.
The power went out at around 12pm and reports suggest that up to 8,000 homes were affected.