 Telmex has diversified its operations by incorporating Internet service and mobile telephony.It has also expanded its operations to Colombia, Peru, Chile, Argentina, Brazil, Uruguay, Ecuador and the United States.Due to Mexican diverse orography—the country is crossed by two high altitude mountain ranges extending from the Rocky Mountains—providing landline telephone service at remote mountainous areas is expensive, and penetration of line-phones per capita is low compared to other Latin American countries, with 20 million lines.