United Kingdom:
total: 16,878 km

broad gauge: 342 km 1.600-m gauge (190 km double track); note - all 1.600-m gauge track, of which 342 km is in common carrier use, and is in Northern Ireland

standard gauge: 16,536 km 1.435-m gauge (4,928 km electrified; 12,591 km double or multiple track) (1996)

United States:
total: 225,750 km mainline routes

standard gauge: 225,750 km 1.435-m gauge (1999)

Uruguay: total: 2,073 km

standard gauge: 2,073 km 1.435-m gauge (2000)

Uzbekistan:
total: 3,380 km in common carrier service; does not
include industrial lines

broad gauge: 3,380 km 1.520-m gauge (300 km electrified) (1993)

Vanuatu:
0 km