According to Wikipedia the current status of the forts is as follows:
- Fort Fareham is now a small industrial estate.
- Fort Wallington has been largely demolished to make way for an industrial estate.
- Fort Nelson has been extensively restored as an artillery museum run by the Royal Armouries.
- Fort Southwick was for many years an Admiralty Research Establishment, sold in 2003 for housing.
- Fort Widley is owned by Portsmouth council, hosting a stable and various community rooms. Tours run on summer weekends.
- Fort Purbrook is open occasionally for craft fairs. It is also home to an activity centre.
There were also two redoubts guarding Fort Purbrook:
- Crookhorn Redoubt suffered from subsidence, and was demolished by 1876.
- Farlington Redoubt had only the ditches and gun positions dug, and was finally demolished in the 1970s.