Runes shown on the front cover (and also in the booklet) are Nordic runes with the Elder Futhark alphabet. On the back cover every song has its own rune character:
"Ginnungagap (Prologue)"
"Midgård"
"Asgård"
"Jotunheim"
"Schwarzalbenheim"
"Ljusalfheim"
"Muspelheim"
"Nifelheim"
"Vanaheim"
"Helheim"
"Secret of the Runes (Epilogue)"
Secret of the Runes title is written in the Elder Futhark alphabet on the front cover as: