Rogers Pass content outlines the history of the Loops. The switchback loop configuration, comprising bridging, embankments, and following the hillside, ensued because the preferred alternatives did not fit the terrain. The Loop Brook trail includes the stone pillars for the crossings south of today's highway. Formerly called Five Mile Creek, the crossing was known as Five Mile Creek Bridge. Water erosion undermining the footing has toppled one of the pillars on the upper crossing. Remnants from the former crossings north of today's highway are inaccessible.