This coastal cycle or walk takes you from Lymington to Keyhaven through the beautiful Keyhaven and Pennington Marshes. The path runs along a sea wall with the marshes on one side and the sea on the other. As such you are surrounded by varied and beautiful scenery for the length of the route. In the marsh area you will pass a number of pretty lagoons where you can look out for a wide variety of birdlife including Egret, Shelduck, Curlew and Heron. On the coastal side there are fabulous views of the Isle of Wight which is less than 2 miles away. Hurst Castle is also visible for most of the way - you could extend your walk by walking along the shingle spit to Henry VIII's Device Fort if you have time.
The Solent Way and the Bournemouth Coast Path long distance walking routes also run through Keyhaven so you could also continue your exercise along these paths.