In English, the voiceless stops/plosives (p, t, k, "hard" c) are aspirated, particularly when beginning a word. That is, speakers release a burst of air when saying pop, tea, kaluha, or coffee (put your hand in front of your mouth and try it).

However, in a Romance language like Spanish, these consonants are unaspirated: very little air is released when pronouncing them (see Is the /p/ sound aspirated in Spanish?).

I'd like to know how these voiceless plosives were pronounced in Classical Latin. Were they aspirated? How do we know?

In English, the voiceless stops/plosives (p, t, k, "hard" c) are aspirated, particularly when beginning a word. That is, speakers release a burst of air when saying pop, tea, kaluha, or coffee (put your hand in front of your mouth and try it).

However, in a Romance language like Spanish, these consonants are unaspirated: very little air is released when pronouncing them (see Is the /p/ sound aspirated in Spanish?).

I'd like to know how these voiceless plosives were pronounced in Classical Latin. Were they aspirated? How do we know?