I went to Seoul for three days as a "layover" to Japan from Europe, to me it was enough time although must guide tell you to spend at least 4-5 days that way you can also day trip to Nami Island for example, Bukhansan National Park, the DMZ, or go to one of the many theme parks.
Important: Download the app Naver App because google maps doesn't work in Korea. Most locals don't speak english either. Buy a sim card at the airport or an online sim card if you want internet constantly.
Tip: Buy skin care products there!
Tip: Choose well where you eat, the food markets are always great but fo example I simply walked into some places and was fed what seemes to be broth and piece of fat, same with the korean bbq.
Tip: to call a taxi/ride use Kakao T app
To Eat:
Myeong dong street at night and perfect for street food! (Recommended the staz hotel)
Seoul sky 118
Gwangjang good market has a famous dumplings woman from netflix chefs table
Gaeseong Traditional Dumpling house (Michelin Star but affordable)
Cafes: pink pool, HP, poop theme, cheongsundung, onion (cake), Cafe Knotted Anguk,
Pancakes: flippers, madang flower, cafe highwaist, water meal, saladaeng bankok
Ocheneonjip (incredible korean meal)
Eat:kimchi, soju (vodka like), rice cakes
Seoulism for the typical photo (cafe)( it’s close to the Olympic park)
Cherry blossom:
Yeouiseo-ro (Yunjung-ro),namsan, Olympic park, Seoul forest park
Nightlife:
Hongdae at night (bars student area)
Architecture:
Jongro Tower, floating islands - have a drink there at Mood Seoul
Itinerary Example:
Day 1
Start in the old historic Seoul
Gyeongbokgung Palace (catch changing of guards, google the time)
Bukchon Hanok Village (a hanok is a traditional Korean house)
changdeokgung palace & changyronggung & secret garden
Gwangjang market or through ihwa graffiti (10m from each other)
National museum of Korea (closes at 18; free)
-> 15 DDP (at night it lights up)
Isadong + ssamziegil market
Day 2
+Jogyesa temple ( has daeungjeon seouls largest Buddhist workshop hall and epicenter of Korean Buddhism completed in ‘38)
Cheonggyecheon
Seoul city hall
Deoksugung
Seoullo 7017
Leem Samsung museum of art (closed monday- free )
Namsan peak sunset (see the N Seoul tower and city wall from here) cable car
Day 3
Starfield library inside coex mall
Gangnam
K-star road and canal
Seoulism
Floating island
More:
Gwacheon: Seoul grand park, Seoul land amusement
Olympic park
Photo Spots:
Yeouiseo-ro (Yunjung-ro)/ Yeouido Park
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Bukchon Hanok Village
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Changdeokgung Palace
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We watched the changing of the guards at Gyeongbokgung Palace, most people had rente a hanbok too
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Typical cream croissants, this particular was in Anguk Knotted Cafe next to Bukchon Village
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Ihwa Mural Village
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Jogyesa Temple
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The National Assembly of Korea
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K-Star Road
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Starfield Library (I didnt make it on time the mall had already closed so the lights were off)
Gangnam
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Gangnam
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Kings Cross Cafe
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Samsung Jong-no Tower
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The Poop cafe
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Gwangjang Market
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Myeongdong street food
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Seoul Tower
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DDP
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Hi