At the Heart of Winter marked a significant evolution in Immortal's sound, featuring cleaner production while maintaining their signature black metal intensity. Released in 1999, this album showcases the band's maturation as songwriters and their ability to create epic, frost-bitten anthems.

The album features some of Immortal's most memorable compositions, including the title track and "Solarfall," which demonstrate their mastery of both speed and atmosphere. The improved production allows each instrument to breathe while preserving the harsh, wintry aesthetic. For extreme metal collectors, this CD represents Immortal at their creative peak. The album's balance of accessibility and extremity makes it perfect for both black metal veterans and newcomers to the genre.