During the rule of President Ferdinand Marcos, traffic jams along the avenue started to build up. Several interchanges were constructed to relieve congestion, including the Balintawak and Magallanes Interchanges at opposite ends of the avenue. Later, with the implementation of the Metro Manila Arterial Road System in 1965, in order to complete the Circumferential Road 4 system, EDSA was extended to Taft Avenue from the South Luzon Expressway (the extension was called F. Rein Avenue), and further to Roxas Boulevard (the extension was called P. Lovina Avenue). EDSA was also extended from its original Balintawak terminus to Apolonio Samson Road at the roundabout containing the Bonifacio Monument in Caloocan, completing the Circumferential Road 4 system. Until the mid-1980s, many parts of the highway still overlooked vast grassland and open fields.