By road, it's about 7.5 miles.
Follow the A202 across Vauxhall Bridge Rd, past Vauxhall station and the Oval cricket ground. Continue along the A202 going through Camberwell and New Cross. Just as you get to Deptford Bridge DLR station, you'll then come to a junction. One route is for the A2 towards Kidbrooke, and the other is the A206 towards Greenwich. Follow the A206 and it'll take you all the way to the Cutty Sark.
If your not up to walking it, consider either the bus or Tube. Bus will take about 1hr 20, where as the Tube will take about 45 minutes. If your taking the bus, catch the route C10 towards Canada Water. At Southwark Park change onto the route 188 towards North Greenwich. Get off at Cutty Sark and walk to the attraction.
If you want to get there quicker, take the Tube and DLR. Circle or District line from Victoria tube station (a short walk up Buckingham Palace Rd from the coach station) to Tower Hill. At Tower Hill walk to Tower Gateway DLR station. Take a DLR train towards Beckton and change at Poplar onto a train going towards Lewisham. This will take you to Cutty Sark DLR station, and from there it's just a short walk to the attraction.
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