Arch Mahjong Solitaire
About the Arch Layout
The Arch is built like a rounded doorway: two solid vertical legs rise from the base and curve inward to meet in a smooth semicircular top, framing an open span underneath. The legs are columns of stacked tiles standing parallel on the left and right, and the crown that bridges them is a graceful half-ring of tiles following the curve. Whether the inner span reads as open air or a lightly filled archway, the defining feature is that hollow center, which gives the board a tall, gateway-like profile rather than a packed mass.
Arch earns a solid 3 out of 5 because of how its weight is distributed. The two legs are dense and deep, while the curved crown is thinner and exposed, so you have plenty of free tiles up top but two stubborn pillars to dismantle below. The shape feels architectural and balanced to play, and the satisfaction comes from collapsing a standing structure: clear the keystone region and watch the whole gateway come down around the two supports.
Difficulty: Hard (3/5) | Tiles: 98
How to Clear the Arch Layout
Start at the crown. The curved top arc is the most exposed part of the layout because its tiles sit highest with open ends along the outer and inner edges of the curve. Clearing the semicircle first removes the cap and begins to expose the tops of both legs, which is where your harder work waits.
Drain both legs in step. The two vertical columns are the depth of this board, and each leg only frees from its top and its outer side. Work them down together rather than emptying one fully, because keeping both legs at similar heights means more side tiles stay reachable and you avoid stranding pairs at the bottom of a single deep pillar.
The crux is the inner edges of the legs facing the open span. Tiles along that inside wall are easy to overlook since the hollow center can make them feel boxed in, but they free up nicely once the crown above is gone. Watch the keystone tiles where the arch meets each leg, as those connect the curve to the columns and can bottleneck if cleared in the wrong order.
For the endgame you will be left with the lower thirds of both legs, two short stacks of tiles standing on the base. These are the deepest tiles on the board, so plan a few moves ahead to make sure each leg's bottom tile has a living twin. If the two pillars lock each other, Shuffle re-deals the remaining tiles solvably.
The Story Behind the Arch Layout
The arch is one of humanity's oldest engineering triumphs, a shape that turns the downward pull of gravity into sideways pressure that the two legs carry to the ground, which is how Roman aqueducts and stone bridges have stood for two thousand years. The keystone at the very top locks the whole curve together, and remove it and the structure fails.
That real-world logic translates beautifully to Mahjong, because the board genuinely behaves like an arch: the crown is the keystone region you clear to bring the whole thing down, and the legs are the load-bearing pillars that hold out longest. Dismantling it tile by tile feels like a careful, reverse act of construction.
Frequently Asked Questions
Should I clear one leg of the Arch completely before the other?
No. Lower both legs together at a similar pace. Each column only frees from its top and outer side, so keeping them even keeps the most side tiles reachable and prevents you from stranding a pair at the bottom of a single deep pillar.
Why are the inner tiles of the Arch hard to reach?
The tiles along the inside walls of the legs face the open span, so they look boxed in and are easy to forget. They actually open up once the curved crown above them is cleared, so remove the top arc first and the inner edges become accessible.
What makes the Arch harder than a solid shape like the Sphere?
The two legs are deep, narrow columns rather than a broad mass, so their bottom tiles surface last and have fewer neighbors to free them. That concentrated depth at the base is the main difficulty and is why Arch rates 3 out of 5.
What is the keystone region and why does it matter?
It is where the curved top meets each leg, the same spot a stone keystone would lock an arch together. Clearing those junction tiles in the right order is what lets the crown come off cleanly and opens both legs at once, so treat them as the hinge of your plan.
See more Geometric Mahjong boards, or browse all layouts.
