Jenin is an old knanis city which was build before 4000 year. Jenin in the north West Bank.
The most logical way to enter would be to fly into Ben Gurion International Airport in Israel, take a taxi or mini-bus to the Tantoer checkpoint right by Bethlehem, cross into Bethlehem and take a taxi to Jenin.
Walking is a practical mode of getting around, taxis can be hired as needed.
Be sure to take advantage of the great bargains that can be found in the many shops. This is a great place to find souveniers!