The Ethereum Go client (https://geth.ethereum.org) Geth, can be connected to the test network using the following command:
$ geth --testnet
A sample output is shown in the following screenshot. The screenshot shows the type of the network chosen and various other pieces of information regarding the blockchain download:
A blockchain explorer for testnet is located at https://ropsten.etherscan.io can be used to trace transactions and blocks on the Ethereum test network.
There are other test networks available too, such as Frontier, Morden, Ropsten, and Rinkeby. Geth ...