City guide
Sepang KUL: 4 Hours, 28 Min to the City
Petronas Towers and roti canai in 4 hours: 20-min train, $1 breakfast, free entry.
Getting from the airport
KUL to city center: 28 minutes by rail (KLIA Ekspres). Fare is $10. Trains run every 15 minutes. Service runs 05:00 to 00:00. Skip the taxi unless your connection is under 5 hours.
What to do in Sepang
The stops worth making: Petronas Towers, Batu Caves, Bukit Bintang street food, Jalan Alor. Rated above 4.4: Merdeka Square (4.5), KLCC Park (4.6), Thean Hou Temple (4.6), Menara Kuala Lumpur (4.5), National Mosque of Malaysia (4.8). You do not need the full tourist circuit. Pick two and commit.
Visa and entry
Sepang is visa-free for US passports. No application, no fee. The border process at KUL is efficient. Expect 15 minutes or less.
How long do you need
The minimum useful layover is 4 hours. That gives you 28 minutes in each direction plus about 94 minutes on the ground. Up to 48 hours is a proper overnight.
KUL airport
KUL has 10 lounges. For short connections under 4 hours, the terminal is the destination: food options, showers, and enough space to reset before the next leg.