Article Detail Which is smallest planet ? Answer: Mercury Similar Questions : 1. Which Indian state is having longest coastline ? Answer: Gujrat 2. Which is Highest Battle field ? Answer: Siachin Glacier. Mastguru team Salutes to Indian soldiers. 3. Which is Largest railway route in India ? Answer: Dibrugarh in Assam to Kannyakumari in Tamil Nadu. 4. Which is Longest road tunnel in the World ? Answer: Lærdal Tunnel (Norway - 24.51 kilometre) 5. What is the name of tallest Animal ? Answer: Giraffe 6. Which is largest continent ? Answer: Asia 7. Longest rail tunnel in the world ? Answer: Seikan Tunnel (Japan - 53.9 Km) Read more from - Longest and Largest