Paris

Paris makes more sense once the arrondissement system clicks. The city spirals out in 20 numbered districts from the 1st, which wraps around the Louvre, clockwise like a snail shell, out to the 20th on the eastern edge. The last two digits of any Paris postal code tell you which one you're in — a hotel in "75011" is in the 11th. It sounds bureaucratic until you're standing on a corner trying to figure out which direction the numbers are heading, and then it's the single most useful fact you'll carry around all trip.

The big sights cluster where you'd expect: the Louvre and Tuileries in the 1st, the Eiffel Tower across the river in the 7th, Notre-Dame and the Latin Quarter around the 4th and 5th. But the neighborhoods that reward slower time — the Marais with its falafel stands and vintage shops, Montmartre's steep streets above Sacré-Cœur, Canal Saint-Martin's newer café scene in the 10th — sit slightly outside that core, and they're where a lot of Paris's actual daily life is happening.

August is a genuine trap for planning if you don't know about it in advance. A large share of independent restaurants, boutiques, and even some smaller museums close for two to four weeks as owners take their own vacation. The big institutional sights — Louvre, Eiffel Tower, Orsay — stay open regardless, so a museum-heavy trip works fine in August, but anyone hoping to work through a list of specific small restaurants should check ahead or consider a different month.

The metro is dense and frequent, though a lot of the older stations, especially in the center, have stairs and no elevators, which matters if you're traveling with heavy luggage or mobility needs. A carnet of paper tickets still works, though the city has been pushing riders toward the Navigo Easy card, which is refillable and slightly cheaper per ride.

Tipping works differently here than a lot of visitors expect. Service is legally included in restaurant prices — service compris shows up on the bill — so the standard American-style 20% tip isn't the norm. Rounding up a euro or two in cash for good service is a nice gesture, not an obligation.