Los Coches Trestle. It was one of 315 trestles that carried the Cuyamaca flume across valleys, canyons and ravines. It was the longest - 1774 feet in length and 56 feet high. Approximately 37 miles long, the flume was built by San Diego Flume Co. 1886-1889. Redwood lumber was brought by boat to San Diego harbor, cut to the required lengths and loaded on wagons for the trip inland. The flume's usefulness eventually was replaced with other water sources and today there are very few remnants of the old line remaining.