Article Detail Longest rail tunnel in the world ? Answer: Seikan Tunnel (Japan - 53.9 Km) Similar Questions : 1. Which is largest Dome in India ? Answer: Gol Gumbaz (Karnataka) 2. Which is the state largest by area in India ? Answer: Rajasthan 3. Which is the highest Plateau ? Answer: Pamir, Tibet 4. Which is the brightest planet ? Answer: Venus 5. Which is the longest Platform ? Answer: Gorakhpur railway station, Uttar Pradesh, India (1355.40 meters) 6. Which is the highest dam in India ? Answer: Tehri Dam on Bhagirathi River in Uttarakhand (Height of 260 metres) 7. Which is smallest planet ? Answer: Mercury Read more from - Longest and Largest