Clava Cairns Passage Grave 2 (Southwest Cairn) mirrors the northeast chamber's construction and astronomical alignment, completing the sophisticated ceremonial landscape that inspired Outlander's mystical stone circle concept. This Bronze Age burial chamber's passage also points toward the midwinter sunset, creating a unified spiritual axis across the entire site that demonstrates ancient Highland understanding of seasonal cycles and astronomical phenomena. The cairn features the same graded kerbstone arrangement - larger, redder stones toward the sunset direction and smaller, white quartz-crystal stones toward the sunrise direction, showing remarkable attention to visual symbolism and spiritual significance. The entrance would be dramatically illuminated by the setting sun on December 21st, creating an otherworldly atmosphere that connects this site to Outlander's themes of time travel and spiritual transformation. This sophisticated prehistoric engineering reflects the advanced culture that flourished in Highland Scotland millennia before the 18th-century setting of the series.