부산 is written Busan on every road sign in South Korea, and the first sound in it is closer to an English p than a b. The spelling the country retired in 2000, Pusan, was the one that got the sound right.
South Korea traded phonetic honesty for a system that maps each hangul letter to a fixed roman letter. Once you know that trade was made, the roman lettering under Korean menus, subway maps and idol names stops working as a pronunciation guide and starts being what it is: a caption for people who cannot read the alphabet yet. Here are the four places the caption misleads you, and the habit that gets you past all four.
Busan or Pusan: the switch that traded sound for spelling
On 7 July 2000, South Korea's Ministry of Culture, Sports and Tourism issued Revised Romanization as Proclamation No. 2000-8, replacing the McCune-Reischauer system that had been standard for decades. 부산 changed spelling overnight.
The two systems answer different questions. McCune-Reischauer tried to write the sound. Korean's plain stops ㄱ, ㄷ, ㅂ and ㅈ are voiced only between sonorants and voiceless everywhere else, so the ㅂ at the front of 부산 comes out voiceless, near the p of English spin. McCune-Reischauer wrote that: Pusan.
Revised Romanization answers a different question. It asks where the letter sits in the syllable, not what the vocal cords are doing. An onset ㅂ is b, in every word, in every position at the front of a syllable. So 부산 is Busan, and the roman line no longer tells you that the sound is voiceless.
부산 never changed. The system that transcribes it did, in 2000.
Write Busan. It has been the standard since 2000, and it is what maps, tickets and signage use. But Pusan is not a typo when you meet it, and it never fully went away: Pusan National University still calls itself that in English and still sits at pusan.ac.kr. The roman spelling of a Korean proper noun tells you roughly which decade it was written down, not how to say it.
Worth separating two questions that share the city's name. This is about how Busan is spelled. How Busan actually sounds when someone from there is talking is a different gap entirely.
비빔밥 has four ㅂ, and the roman line gives you b, b, b, p
비빔밥 has four ㅂ in its hangul, and the roman spelling turns them into three b's and a p. 비 is ㅂ + ㅣ. 빔 is ㅂ + ㅣ + ㅁ. 밥 is ㅂ + ㅏ + ㅂ, carrying one at the top and another at the bottom. Four identical letters, and the official spelling is bibimbap.
Here is the rule that produced that, and it is the one piece of this worth memorizing:
ㄱ, ㄷ and ㅂ are written g, d and b before a vowel, and k, t and p before a consonant or at the end of a word. The National Institute of Korean Language, which issues the system, states it exactly that way.
So the three ㅂ that open a syllable become b, b, b. The fourth one closes 밥 at the end of the word, so it becomes p. Same letter, four times, two roman spellings, and nothing about the food changed in between.
Now put the actual sounds beside them. The first ㅂ is word-initial and voiceless, near [p]. The second sits between vowels and is genuinely voiced, [b]. The third follows the nasal ㅁ, also voiced, [b]. The fourth is a word-final stop that never gets released, [p̚].
So the roman line reads b, b, b, p while your mouth does p, b, b, p. Exactly one letter lies, and it lies in the most conspicuous spot in the word: the very first sound. McCune-Reischauer, for its part, wrote the whole thing pibimpap.
A word-initial plain ㅂ is voiceless. The b in the roman line marks the letter's position, not the sound.
The same rule runs through 떡볶이, romanized tteokbokki. The ㄱ at the bottom of 떡 closes its syllable, so it is written k. The ㅂ that opens 볶 is written b. Two rules, one snack.
One correction to a pattern learners often extend too far: this alternation covers three consonants, not four. ㅈ has no matching "ch" ending. At the end of a syllable ㅈ neutralizes to an unreleased [t̚] along with ㅅ, ㅆ, ㅊ and ㅌ, and gets written t. The Institute's rules list the alternation for ㄱ, ㄷ and ㅂ only.
Jung-ang, not Jun-gang: the hyphen doing real work
중앙 is two syllables, 중 and 앙, and Revised Romanization writes it Jung-ang. Take the hyphen out and an English reader gets "Jungang", which reads naturally as Jun-gang: wrong syllable break, wrong word. The hyphen is the only thing marking where one block ends.
해운대, the beach district in Busan, does the same thing. It is 해 + 운 + 대, written Hae-undae. Without the hyphen, English eyes land on Haeun-dae.
Signs are inconsistent about this because the rules are. The Institute makes hyphens mandatory for administrative units like -do, -si and -gun, and merely permits them elsewhere to prevent exactly this kind of misreading. Permitted things get dropped. Geographic features take no hyphen at all: 설악산 is Seoraksan, run together.
The frustrating part: the system is honest sometimes and not others, so there is no rule of thumb to fall back on. Revised Romanization does rewrite for pronunciation in other places, and quietly. 신라 becomes Silla rather than a letter-by-letter "Sinra". 종로 becomes Jongno rather than "Jongro". 좋고 becomes joko, with a single k, because the ㅎ and the ㄱ fuse into one aspirated sound.
So the roman line applies sound changes across syllable boundaries, then declines to mention that a word-initial b is voiceless.
While you are here: "eo" is one vowel, ㅓ, and "eu" is one vowel, ㅡ. Neither is two sounds glued together, which is why 서울 is not "See-oul". Retraining your ear on those vowel pairs is a separate job. Retraining your eyes takes about a minute: when you see eo or eu, read one vowel.
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Try Conversa FreeKimchi and gamja start with the same letter
김치 and 감자 both open with ㄱ in the same position. By the rules, they are gimchi and gamja. English uses the g for the potato and a k for the cabbage, and there is no phonetic reason for the split. Kimchi is simply the pre-2000 spelling that English had already adopted and saw no reason to change, the way English keeps any loanword spelling it picked up early.
Names work by a different mechanism, and that one is written into the system rather than being convention. The Institute's rules state that proper names such as personal names and company names may be written as they have been:
Personal and company names were allowed to keep the spelling they already had.
Korean names you meet through music and television stack several of these at once. The actor 박보검 is Bak Bogeom by the rules and is written Park Bo-gum everywhere in English: the frozen Bak-to-Park swap, an r that corresponds to no Korean letter, and eo rewritten as u.
BTS's 정국 is Jeongguk, where the final syllable 국 is ㄱ + ㅜ + ㄱ, the same letter romanized g at the front and k at the back, inside one syllable. His stage spelling, Jung Kook, swaps the eo for a u as well.
None of this is decodable. It is a memorize-and-move-on list, and it is short.
The sign test
Cover the roman line on a menu, a subway map or an album tracklist. Read the hangul out loud. Then uncover the roman line and name which letter lied.
On 비빔밥 the answer is the first b. On 해운대 it is the missing hyphen. On 김치 it is the whole word, adopted into English decades ago. Do this ten times over one lunch and the roman line stops steering your mouth. That is the entire goal.
Say 비빔밥 out loud to something that answers back, like an AI conversation partner such as Conversa, and a first sound that lands like bed instead of spin is exactly the kind of miss your eyes will never catch on their own.
This only works once you can read hangul, and there is no version of it that works before that. Learning the alphabet is a weekend, not a semester, and it is the best-spent weekend you will put into Korean.
Two of these traps have a second layer worth reading later: the plain, aspirated and tense consonants that romanization flattens, and the ㄹ behind Silla and 라면.
So: Busan is correct, Pusan is not wrong so much as retired, and the first sound in the city's name has been the same all along. The letters moved. 부산 never did.