Senegal is a country in Western Africa. With the Atlantic Ocean to the west, Senegal has Guinea-Bissau to the south, Guinea to the southeast, Mali to the east, and Mauritania to the north. The Gambia is almost an enclave of Senegal in the middle of the western coast.
It is recommended that your passport is valid for at least 90 days following your departure date. In addition, most destinations require that you have adequate un-used pages in your passport, allowing for any necessary stamps upon arrival and departure. Check the visa requirements for Senegal here