Phase Two consists of the emergence of few major lines of penetration, the a growth of inland trading centres at the terminals, and the differential growth of coastal ports with inland connections (Figure 3.23B). With the growth of the coastal ports, the local hinterland also expands and diagonal routes begin t focus the ports. Again the phase is identified in Ghana and Nigeria on growing with the growth of inland trunk routes. These appear to have been built inland for three major reasons: (i) to connect a coastal administrative centre politically and militarily with its sphere of authority up-country, e-g.in Ghana Ashanti; (ii) to tap the desire to reach Kumasi, capital of the rebellious exploitable mineral resources, such as the Enugu coalfields in Nigeria; and (iii) to tap areas of potential agricultural export production, such as the cocoa areas north of Accra. Although each motive has played its part, the role of mineral exploitation has been a critical one in African railway building and from Uganda (Kasese copper line), the Cameroons (Garoua examples manganese line), and Mauritania (Fort Gourard iron-ore line) suggest that this phase has not yet ended.