A city that feels better than it explains
Bangkok is not "visited". It is experienced on the go, between a skytrain, a narrow street full of the smell of lime and chili, and a rooftop where the city looks, for a few minutes, like a luminous model. 100 hours are enough to feel it, if you don't try to do it "completely".
Start with an early morning on the river. The Chao Phraya is the easiest way to get around: pass by temples, old hotels, markets, and see how Bangkok changes with each stop. Get off at Wat Pho and Wat Arun, but leave room for breaks. The heat is not a detail, it's part of the program, and Bangkok is best experienced at a slow pace: get out, see, get in the air conditioning, start again.
Afternoons are for the neighborhoods. In Talat Noi and Chinatown, the city is dense and photogenic without being "arranged": workshops, discreet graffiti, small cafes, noise, then, suddenly, a quiet corner. If you want to shop, Bangkok does it very well, but the contrast is interesting: an impeccable mall at Siam, then a night market where you eat on the go, without caring how it will look on your Instagram feed.
Save one night for serious street food. You don't have to make it a hunt. Pick an area (Chinatown is an easy choice), follow the lines of locals, and eat a little, often. Bangkok has the kind of food that makes you want more even when you're out of room.
A day trip to Ayutthaya gives you a different perspective of Thailand: ruins, tranquility, space. And before you leave, don't forget to see Bangkok from above: not necessarily the most famous rooftop, but a good one, with an overview and without crowds.
And at that moment, everything will become a clear image: river, light, traffic, tempo.
100 hours in Bangkok is enough to leave with a few favorite places, not a finished list.