Intramuros — the 400-year-old walled city the Spanish built. Fort Santiago entry is about ₱75 ($1.20), and the cathedral and San Agustin Church (a UNESCO site) sit inside the walls. Tour it by bamboo bicycle or a kalesa horse cart, or join one of the theatrical walking tours that run most evenings.
National Museum Complex — the National Museums of Fine Arts, Anthropology and Natural History face Rizal Park and are all free. The Natural History building's glass 'Tree of Life' dome is the architectural star. Closed Mondays.
Manila Bay sunset — the bay faces due west, and the nightly show is free from the Baywalk or, more comfortably, from a cafe at the Mall of Asia complex. Aim to be waterside by 5:30pm.
SM Mall of Asia — one of the world's largest malls, with an IKEA, an ice rink and a seaside amusement park with a giant ferris wheel (rides about ₱150 / $2.40). Handy for the airport side of town and rainy afternoons.
Binondo food walk — the world's oldest Chinatown, founded in 1594. Guided food crawls run about ₱1,500-₱2,500 ($24-$40), with dumpling and hopia stops included. Vegetarians should flag it when booking — pork is everywhere here.
Day trip to Tagaytay — 2 hours south for the view over Taal volcano in its lake. Day tours run about ₱2,000-₱3,500 ($32-$56), often with a Sky Ranch stop for kids. The best single day trip from the capital.
Corregidor Island — the WWII fortress at the mouth of Manila Bay, reached by ferry with a guided tram tour of the gun batteries and the Malinta Tunnel. It is a full-day commitment and only worth it if the history interests you; check ferry schedules ahead, as they have changed often in recent years.
Skip Manila Ocean Park if you have seen any major aquarium elsewhere — it is small for the ₱700+ ($11) ticket.