Safeplace
Safeplace was a ring world located about 32,000 light-years from Mars. It was a haven for refugees of a galactic war, including the Valdigian species. It was a place where, according to Wembik, "everything's plentiful" and "we don't need kings".
A segment of the Key to Time took the form of a castle where the Valdigians negotiated. Zara had spent years using the Valdigians to find out where the segment was. 16,000 years after Mars became uninhabitable, a group of Ice Warriors arrived, also under the guidance of Zara, to find the segment and attacked the castle. When Zara realised the castle was the segment, it was converted into a crystal form and had the people inside, including the Ice Warriors and Valdigians, trapped. While trying to take Amy's segment, Amy had received the segment and had it turned back into a castle so those inside could escape and recover. She then turned the segment back into a crystal again and placed it inside her satchel. The Ice Lord Isskar took the Fifth Doctor and Amy aboard his ship to face tribunal. (AUDIO: The Judgement of Isskar)