These images show what St. Ninian's Hall looks like at the moment, and how it is expected to look once the development work is completed.
These artist's impressions show the annex due to be built on to the side of the hall, providing space for a new cafe, public toilets and a retail store.
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The historic event always takes place on the last Friday in July.
Early enquiries suggest the men may have taken the drug Blue Valium. Two of them remain in hospital with breathing problems.
More than 8,000 people are expected to attend over the three day event, which starts at 7pm tonight.