The Glen Grant Single Malt Scotch Whisky, nestled in the heart of Speyside, today unveils The Glasshouse Collection: a new prestige range featuring the oldest aged expressions ever in the distillery's permanent collection. The Glen Grant 21-Year-Old is joined by The Glen Grant 25-Year-Old and 30-Year-Old Single Malt Scotch Whiskies to form a collection of rare single malts which celebrate the unparalleled aging of whiskies from the over 180-year-old distillery.