The walled city of Intramuros build by the Spanish to keep out foreign invaders should be on your itinerary. Within the walls, you can do an easy full day walking tour by visiting Fort Santiago and the Rizal Museum located within the premises of the latter and just across Fort Santiago is the Manila Cathedral, which is the prime basilica of the Philippines.
Afterwards head to the opulent Casa Manila, a reconstruction of a Spanish colonial houses and end the tour with a visit to the oldest church in the Philippines: the San Augustin church.
Two museums in Manila are well worth a visit. The National Museum of the Philippines is hosted in the old Congress Building and showcases paintings of Filipino masters. The adjacent building is the former Ministry of Finance and currently houses the National Museum of the Filipino people. The museum includes the skull of the Philippines earliest known inhabitant as well as treasures recovered from a Spanish galleon.
A trip to Manila is not complete without visiting a Mall. The Mall of Asia is one of the largest malls in the world and boasts a dazzling range of shops and entertainment options. The well stocked foodcourt offers cheap and good eats, while in the IMAX cinema you can give your legs some well deserved rest after hours of hard shopping.
A large congregation of fine restaurants and fashionable bars and nightclubs can be found in the Fort Bonifacio Entertainment Center (or the Fort) in Makati as well as in nearby Serendra. Get a taste of traditional Filipino food in Abe restaurant in Serendra and indulge your taste buds with a delicious Pork Sinigang. After that dance and drink the night away in the Archema with its 5 bars and 2 dance floors divided over three floors.
Corregidor island strategically located in the bay of Manila has been the scene of many battles throughout history and was involved in both WWII and in the American-Spanish war. There are several fortresses, tunnels and war relics scattered over the island, as well as a hotel and attached restaurant. Day tours from Manila are leaving from the Cultural Center of the Philippines on Roxas boulevard. Tour agencies have 3 day tours including accommodation in the Corregidor hotel and buffet style eating.