When travelling, it is always advisable to have good communications, especially when away from civilisation. There are different options, and all have their good points and limitations.
CB radios come in 2 flavours, HF (High Frequency) and UHF (Ultra High Frequency).
HF is the original CB band, and uses 27MHz. When the conditions are right, then it is possible to communicate over large distances, although not always reliably.