A subterranean housing and post system for connection to a traffic guardrail is disclosed. The housing comprises an interior space and a soil plate extending outward from the housing. The interior of the housing comprises a lower post guide, a lower post stop, and an upper post stop. A lower post has a U-channel shape with outwardly extending flanges. The lower post is insertable into the lower end of the housing, between the lower post guide and the housing body, with insertion limited by engagement with the lower post stop. An upper post has a U-channel shape with outwardly extending flanges. The upper post is insertable into the upper end of the housing, between the lower post and the housing body. Insertion of the upper post is limited by engagement with the upper post stop. The upper post is connectable to a guardrail.