 Work began in 1835 on a tramway up the valley, but Austen and his steward William Pease realised that it was not going to meet their ambitions, so it was abandoned and only a few fragments of the route are visible today.Instead, they built a much larger-scale tramway, with the inclined plane from the canal basin, past the Carmears Rocks, to the level of the top of the valley, then a level run through Luxulyan and on to its terminus at the Bugle Inn near Mollinis.This required a high-level crossing of the river, for which they built the great viaduct, 650 feet (198 m) long and 100 feet (30 m) high, the most advanced engineering project in the western peninsula.