Forty international carriers connect Karachi by Air with all the major cities of the world. PlA's domestic network provides convenient flights to the rest of the country. There are several smaller domestic airlines. These connect Karachi with main cities. Pakistan Railways run several Express trains to the various points daily It is also connected with the National Road Network with direct roads to Quetta and onward to Iran. Shipping services are offered for Europe. The Middle East and South East Asia, Inward traffic by sea, however are negligible.