[sim-plon; Fr. san-plawn] 
| 1. | a mountain pass in S Switzerland, in the Lepontine Alps: crossed by a carriage road constructed 1800–06 on Napoleon's orders. 6592 ft. (2010 m) high. |
| 2. | a tunnel between Switzerland and Italy, NE of the Simplon Pass: longest tunnel in the world. 12 1/4 mi. (20 km) long. |
plɒn