Coordinates : 50 ° 43 ′ 30 ″ N 2 ° 56 ′ 24 ″ W \ / 50.725 ° N 2.940 ° W \ / 50.725 ; -2.940 Lyme Regis \ / ˌlaɪmˈriːdʒɪs \ / is a coastal town in West Dorset , England , situated 25 miles west of Dorchester and 25 miles ( 40 km ) east of Exeter .
Coordinates : 50 ° 43 ′ 30 ″ N 2 ° 56 ′ 24 ″ W \ / 50.725 ° N 2.940 ° W \ / 50.725 ; -2.940 Lyme Regis is a coastal town in West Dorset , England , 25 miles west of Dorchester and 25 miles ( 40 km ) east of Exeter .