To join the Lightning Network, it is required for either you or your peer to make at least one on-chain transaction, which incurs the regular transaction fees of the underlying blockchain. The two parties can then transact infinitely with each other at no cost. For a peer to route payments onwards to their peers, however, the peer typically charges a small fee. For a payment that traverses multiple hops, this fee is levied multiple times by each router. Fees are known in advance of attempting the payment, and, as the payer chooses the route also based on fees, competition ensures the network remains cost competitive.