Forgive my ignorance on matters related to the Philippines, but as I look at some of these pictures, it seems that all of the highway signs are in English and apparently English only. Isn't the native Filipino language more commonly spoken than English? Why aren't there more signs in Filipino or at least bilingual English/Filipino signs?
The "Motorsiklo" signs along EDSA are in Tagalog but yeah that is absolutely noticeable.
English is prevalent enough in the Philippines that my guess is that they are attempting to go for international signage standards, where some of the words are going to be the same in English and Tagalog (i.e. exit, km). Some filipino English quirks can be seen in the location signs (i.e. "You are now in San Juan River" on SS3)
The new Skyway overhead signage San Miguel Corporation has installed between NAIAX and Nagtahan all are to modern Interstate standards, but north of there it is still mostly small pole-mounted stuff that will eventually be hard to read once fully freeway speeds of 80km/50 MPH are allowed in Stage 3.
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