A bit about the groups taking part on the day.

Trigpoint Hillwalking has been providing training in lowland hillwalking and navigation with ongoing advice and support, since 2002, for anyone from the beginner wanting to find out what it's all about to the seasoned walker wanting to brush up on their land navigation skills.
Each course takes between five and ten students to allow appropriate group and one on one interaction.
All our courses are presented and supported by indoor lectures, demonstrations and exercises with the afternoons being spent on the Southdowns with practical tasks and the application of skills learnt in the "classroom" that morning.
The National Trust is a charity and is completely independent of Government. We rely for income on membership fees, donations and legacies, and revenue raised from our commercial operations.
We now have 3.5 million members and 43,000 volunteers. More than 12 million people visit our pay for entry properties, while an estimated 50 million visit our open air properties.
We protect and open to the public over 300 historic houses and gardens and 49 industrial monuments and mills.
But it doesn’t stop there. We also look after forests, woods, fens, beaches, farmland, downs, moorland, islands, archaeological remains, castles, nature reserves, villages - for ever, for everyone.
Experience some of our finest countryside between Winchester, first capital of England, and the white chalk cliffs of Eastbourne. If you are interested in great views, attractive wildlife, visible prehistory, fine pubs and pretty villages, or if you just fancy a challenge, the South Downs Way awaits you.
Southdown's Orienteers

Southdowns Orienteers is the orienteering club for Sussex and was formed in 1976. This friendly local club offers regular events in forests and other interesting areas across Sussex on Saturday mornings for all age groups and abilities. It doesn't matter how young, old or fit you are, as you can run, walk or jog the course and progress at your own pace. The club has a strong family membership and groups can take part together. Parents can take delight from watching their children gain confidence and learn skills in map reading and spacial awareness. Athletes can compete against the expert navigators for the quickest time. Anyone can get addicted and will enjoy the challenge of a new forest and a new course!
Healthwalks are a great way to be more active, get out in the fresh air and make new friends. They are ideal for those who want to start exercising in a gentle and safe way, as well as those who want to walk regularly, but don't have the time to attend longer walks.
There are twelve regular walks across the city, and lengths range from under a mile (average walking time: 20-30 minutes) to three-four miles (average walking time one and a half to two hours walking time). They are all free, led by trained Volunteer Walk Leaders and are also accessible by public transport.
Brighton & Hove Archeological Society
We are an amateur archaeological society based in the Brighton and Hove area, in the county of Sussex in England (inaugurated in 1906). We promote the study of archaeology and local history and to ensure the proper recording and preservation of local antiquities and relics.
During the Winter months we have a varied lecture programme on a wide range of archeological topics and in addition our associated Local History Group also runs a lecture programme. During the Summer we organize excursions for our members to some of the more unusual or hard to find historical sites in the South.
The society has a very active Field Unit. Apart from "digging" our own site, we assist other groups and professional archaeologists during the season.
We support a number of training courses to help our members become more knowledgeable and proficient by arranging training and qualifications in archaeology.