Plans for the conservation of Whittington Castle near Oswestry are on show in the village.
English Heritage still classify the castle as being in poor condition.
Experts have spent six months drawing up a preservation scheme for the building which is on English Heritage's "at risk" register.
The trustees need to raise more than £1m to restore the castle, which dates back to the 13th century.
The results of their efforts were on display at the Community Centre in Whittington on Saturday.
The Whittington Castle Preservation Trust was established in 1998 with the aim of halting the decline.
They gained a 99-year lease of the castle in 2002.
Although some emergency work has been completed, English Heritage still classify the Grade I listed structure as being in poor condition.
Project manager Sula Rayska said the research was essential in their attempt to getting the funding.