To Cover Large or Busy Areas, Consider Creating a Wi-Fi Mesh Network
If you want to offer wireless Internet in an area that will require more than a few access points (APs), you might consider installing a wireless mesh network.
The APs are called mesh nodes and, unlike a traditional Wi-Fi network, don't have to be wired back to the network router or switch.
At least one mesh node must be connected to the network/Internet; they are called gateway nodes. The other nodes then get their connection via the air waves, the traffic hops from one node to another until it reaches the gateway or destination node. The route to or from a gateway can change; it automatically chooses the best path.
Setting up a mesh network can require less time and money because you don't have to run all the cables. It's great for locations where changes can affect the radio environment because mesh nodes have redundancy features. For low-cost mesh solutions, look into Open-Mesh.