Connect all islands with bridges to form a single network.
How to Play
Tap the space between two islands to place a bridge.
Tap again to upgrade to a double bridge.
Tap once more to remove. (Tap: add → double → remove)
Bridge Count Rule
Each island's number shows the total bridges it needs. A double bridge counts as 2.
No Crossing Rule
Bridges run horizontally or vertically only, and they cannot cross each other.
Completed Example
Each island's number tells you how many bridges connect to it. Double bridges count as 2.
At most two bridges (a double bridge) can be placed between any pair of islands.
All islands must be connected into a single unified network through the bridges.
Tip
Start with high-numbered islands (4+) or islands on corners and edges — their possible connections are more constrained.
If an island has only one reachable neighbor, all its bridges must go there. Use this to make forced moves first.
Completed islands (green) cannot accept more bridges. Use them to narrow down possibilities for neighboring islands.
Bridges puzzles train graph-based spatial reasoning and network connectivity thinking. Structural problem-solving of this kind activates planning functions in the prefrontal cortex and exercises working memory.
Unterrainer, J.M. et al. (2004). Planning abilities and the Tower of London: is this task measuring a discrete cognitive function? Journal of Clinical and Experimental Neuropsychology, 26(6), 846-856.