A Columbia Gorge landmark is turning 100, and Cascade Locks is marking the occasion this weekend.  The Bridge of the Gods will celebrate its centennial Saturday with a festival at Marine Park. The celebration runs from noon to 8 p.m. and includes live music, historical presentations, family activities, a vintage car show and local vendors.  The steel bridge opened in 1926.  The bridge also stands near the site of a much older natural crossing. Native American oral histories describe a land bridge across the Columbia, while researchers believe it may have been formed by a massive landslide from Mount Hood.