Bridges #509 · 7×7

• 7×7grid
• 9islands
• 11bridges
• 3double routes

Bridges #509 is a 7×7 grid at easy level with 9 islands. The solution lays 11 bridges along 8 routes, and 3 of those routes carry a double bridge. The largest number on the map is 4.

You can start without any guessing: 4 islands have a number equal to or one below twice the neighbours they can see, so every one of those neighbours gets at least one bridge.

2 islands carry a 1. Two of them may never be linked to each other, because that pair would be cut off from the rest of the map.

Easy grids can be finished by counting neighbours alone. If you get stuck, look for islands whose remaining number equals what their open neighbours can still take.