hillrock Solera Bourbon World's First Solera Aged Bourbon Distiller Note - "'Solera' - a stack of barrels where a small portion of whiskey is removed periodically and new whiskey is added. No barrel is ever fully emptied, and age and complexity gradually increase over time. Hillrock marries small barrel-aged Hillrock Estate Bourbon with mature seed bourbon before finishing in 20 year old Oloroso Sherry casks to balance flavors and add layers of complexity.