Research Reef in La Union, Philippines, is a marine reef site featuring varied topography, including swim-throughs and channels. Divers can explore depths ranging from 3 to 25 metres, with an average depth of 20 metres. The site is accessible only by boat and is suited for intermediate divers. Conditions are generally favourable, with mild currents and visibility ranging from 15 to 50 metres. Water temperatures remain warm throughout the year, typically between 28C and 31C. The reef structure supports a variety of hard and soft corals, providing habitat for diverse reef fish and invertebrates typical of the region.

Lingsat Marine Protected Area in La Union, Philippines, features a gently sloping reef that begins in shallow water at 5 metres and extends to a maximum depth of 35 metres. The site is accessible only by boat and is suitable for both beginners and experienced divers. Conditions are generally stable with mild currents, though divers should remain aware of boat traffic and depth limits. Water temperatures remain warm throughout the year, ranging between 28C and 31C. The topography consists of a long, sloping reef structure that supports a variety of marine life across its depth range.

Fagg Reef is an offshore pinnacle located in La Union, Philippines, featuring a combination of reef, wall, and wreck topography. Divers enter at 10 metres and follow a steep wall that drops into deeper water. The site is notable for four World War II military tanks resting at an average depth of 42 metres, with the site reaching depths between 39 and 60 metres. Due to the significant depth, overhead environment, and strong currents, this site is strictly for advanced divers. Boat access is required to reach the location, where visibility typically ranges from 10 to 25 metres and water temperatures remain between 28 and 31 degrees Celsius.

Holcim Sanctuary in La Union, Philippines, is a marine site featuring a reef system punctuated by caves and tunnels. Located north of the Sanctuary area in front of the cement factory, the site offers a varied topography suitable for intermediate divers. Depths reach a maximum of 25 metres. Access is strictly by boat. Divers should be prepared for mild currents and the specific hazards associated with an overhead environment when entering the cave structures. Water temperatures remain warm throughout the year, ranging from 27C to 31C.

Paraoir Sur in La Union, Philippines, features a combination of sloping and vertical walls interspersed with large boulders and rock formations. These structures create various cracks and tunnels for divers to explore. The site reaches depths between 5 and 30 metres, with the wall base at 24 metres transitioning into a mix of boulders and sandy patches. Access is by boat only. Conditions are generally stable with mild currents and visibility reaching up to 50 metres. Water temperatures range from 27C to 31C throughout the year. Due to the depth and potential for boat traffic, this site is best suited for intermediate divers.

Paraoir Norte in La Union, Philippines, offers a diverse underwater landscape featuring a wall, reef, muck, and cave topography. Divers can explore swim-throughs and mini-caves at 15 metres, while the wall descends to a maximum depth of 25 metres. The site is accessed by boat, with the top of the wall starting at 8 metres. Conditions include moderate currents, with potential for surf and surge. This site is suitable for beginners, though divers should be prepared for varying water conditions. Water temperatures remain warm throughout the year, ranging from 27C to 31C.

Coral Garden in La Union, Philippines, is a shore-entry site featuring a combination of natural reef and artificial reef structures. The site offers a varied underwater landscape suitable for beginner divers, with depths ranging from 5 to 30 metres and an average depth of 10 metres. Conditions vary, with visibility between 3 and 25 metres and mild currents. Water temperatures remain warm, between 28 and 31 degrees Celsius throughout the year. Divers should exercise caution during shore entry, as sharp coral and rocks are present in the shallow sections. Typical dives last approximately 50 minutes.