The start of the walk is identified as the corner of East Street where it meets the sea front, but wherever you start from simply make your way to the front and walk south along the promenade in the direction of Walberswick (keep sea to your left) and along the sand dunes or sea shore until you reach the harbour entrance. This marks the end point of the River Blyth.
Turn right and walk up Ferry Road until you get to the Harbour Inn. You will pass the ferry (a rowing boat that takes foot passengers between Southwold Harbour and Walberswick), all sorts of fishing boats and stores, pleasure boats and the home of the Coastal Voyager (great fun if you want a short high speed trip around Sole Bay).
Once at the Inn follow the path alongside the river until you reach the metal bridge that crosses the Blyth. This is the old Southwold Railway bridge, a light railway opened in 1879 that ran from Halesworth to Southwold but closed in 1929.

Turn left and walk over the bridge, but do pause to look up river. Tinkers Marshes are on the left and Reydon Marshes on the right. Follow the obvious and well worn path which is the old railway track. The path starts to curve away to the left once through the marshes - there's a small car park and seat here. The old railway track-bed continues straight on so turn off the metalled path and take the path over Walberswick Common. Just imagine yourself going straight on rather than curving away to the left to get directly to Walberswick village.
You can either walk through the old railway cutting (which I prefer) or along the common just to the left of the trackbed. Go through the gate adjacent to the sign welcoming you to Walberswick National Nature Reserve and continue straight on until you reach the road and Eastwoodlodge Farm will be just to your right. Walk along the road briefly until you reach the path on the left that crosses the corner of the field opposite the farm. This takes you to another gate and Walberswick National Nature Reserve sign.
Once through this gate go straight on for a short way until you reach the corner of the woodland. The path goes to the left of the wood, down a slight slope keeping the wood on your right and then curves round to the left, slightly uphill and to the Lodge Road gate.

Cross Lodge Road and follow the track. Do not take the first path to the left that skirts round the field but get to the gate just ahead and go left. If you go through the gate and straight on you will get to the right place a bit later - just turn left when the track meets the marshes.
This will take you out into the marshes along a broad track. Walk along this following the track past the derelict wind pump base and follow the signs for Suffolk Coast and Heaths Path.

Follow the path round the back of Dingle Great Hill, keeping to the Suffolk Coast Path signs. This is not that much of a hill as hills go but is certainly a little higher than the surrounding marshes! Head along the path (going inland) and past Sandymount Covert to get to a well defined track that goes past a chocolate box farm, through a small wooded area and then along a straight track to go past Dingle Stone House, continuing along the track until you go past Bridge Farm at Dunwich. Turn left along the main road until you get into the village centre.

The return from Dunwich to Southwold is simply to follow the coast back to Walberswick, head back inland up the path alongside the River Blyth and back through Southwold.
Approximately half way along the coat between Dunwich and Walberswick a path can take you back inland and over the marshes if you would prefer not to walk along the beach as it can be hard going over sand, although there is plenty of path to make it easier.
In Walberswick the ferry across the Blyth can cut out the chunk walking up the river - this service operates daily from June to the end of September but only operates at weekends and some holidays at other times of the year. If you do use the ferry turn right off the ferry and walk along the sand dunes back to Southwold.

Really easy enjoyable walk.

Nice walk but think it might be a little more than 10 miles