I think last May, you’ve come across a Philippine High Speed Railway System Concept that became viral in the internet. Here is the photo of the system map.
Studying the system, I’ve come to re-draw the system, eliminating what’s totally not feasible given our archipelagic nature.
Not Feasible due to Seismic, Geological, Environmental and Financial Concerns (We have Critical Seabeds greater than 20m here!)
Red Line from Laoag to Palawan (How the can you connect Luzon to Palawan that is hundreds of kilometers away?)
Blue Line from Manila to Tawi Tawi (Also connectin Zamboanga to Tawi Tawi is also costly)
Green Line from Sorsogon to Pueto Princesa (Same with connecting Palawan)
Orange Line from Tacloban to Cebu (Though Visayas are connected by somehow shallow waters, coral reef destruction is the greatest issue here.)
The remaining lines (Violet, Pink and Dark Green Line) are kind of feasible and as some segments of the above lines. Rationalizing it, and emphasizing the International Airport and Seaport Connections, we’ll have:
My concept closely resembles the first one but deleting those impossible to materialize in the Engineering and Financial aspects. Also, the expansion also took account the current plans of the administration when regards to building railway. The Duterte administration want to build 4 lines in Luzon (Manila - Batangas, Manila - Sorsogon, Manila - N. Vizcaya, Manila - San Fernando) and another in Mindanao. I also added a line in Samar/Leyte Islands to continuously connect all lines in Luzon, Visayas and Mindanao.
So we are there, we can connect the three major island groups without even building bridges between islands. We can either connect passengers from e.g. Sorsogon to Allen, Samar in a Ro-Ro or connect the passengers in a fast ferry that will take them to the other Island for free. To connect these two seamlessly is another Engineering Challenge. See Interisland Systems just like in New Zealand.
Also, the lines serving the corridor from Tarlac to Calamba should be separated. These adjoining places is still expected to experience high volume of passenger and freight train so multiple tracking should be done to accomodate such volume.
Also, see in the system that cities with airplane and seaport labels signify that an airport and seaport is in the same spot making this one more integrated to other forms of transport available.
I deleted the other impossible lines but I also have to highlight that we should improve interisland transport services (RoRo and Ferries) already available to these regions.