In 1805–09 a group of Cornish miners, including Richard Trevithick, tried to dig a tunnel farther upriver between Rotherhithe and Wapping/Limehouse but failed because of the difficult conditions of the ground. The Cornish miners were used to hard rock and did not modify their methods for soft clay and quicksand. This Thames Archway project was abandoned after the initial pilot tunnel (a 'driftway') flooded twice when 1,000 feet (305 m) of a total of 1,200 feet (366 m) had been dug. It only measured 2–3 feet by 5 feet (61–91 cm by 1.5 m), and was intended as the drain for a larger tunnel for passenger use. The failure of the Thames Archway project led engineers to conclude that "an underground tunnel is impracticable".