Portobello Road is London's most famous market street, running from Notting Hill Gate north to Ladbroke Grove. Saturday is the main event for antiques — hundreds of dealers spread across stalls and shops from early morning, selling silverware, ceramics, vintage clothing, prints, and improbable objects. The pricing is generally tourist-facing so bargaining or turning up late in the afternoon can help.
The general market (fruit, vegetables, bric-a-brac) runs through the week. The stretch under the Westway flyover tends to be cheaper and more interesting for vintage clothing than the antiques section.
Nearest tube: Notting Hill Gate.