United States itineraries: 1 week, 2 weeks and 3 weeks

The United States is continent-sized, so the itinerary question is really a distance question. A first trip works best as one coast with two or three bases, not a list of cities spread across the map. Every extra region costs a flight, an airport transfer and half a day.

Use the parent country rule: fly any leg over about 600 km, drive within a region. That single rule removes most bad plans. New York to Washington, DC is a train ride; Las Vegas to the Grand Canyon is a drive; New York to Los Angeles is a flight, never a road trip inside a one-week plan.

Then match the region to the season. The Northeast is best April to June and September to December; the Southwest parks March to May and September to October; Yellowstone June to September; Miami and the Keys December to April. A route that fights the season will be the trip you remember for the wrong reason.

These are the shapes the site already recommends at country level, expanded with nights per stop. Treat nights as minimums: adding one night to a park or a big city almost always beats adding a fourth city.

New York 4 nights plus Washington, DC 3 nights is the lowest-risk first week in the country. No car, one train, two airports, and the two cities cover museums, monuments, neighbourhoods and Broadway. Stay in Manhattan and group sights by neighbourhood rather than crossing town twice a day.

Take Amtrak from New York to Washington, DC: about 3 h city centre to city centre (check schedules and fares). Book early for the cheapest seats. Fly home from Washington, DC rather than doubling back, which is usually cheaper than it sounds.

If you prefer a smaller, cheaper base, Rochester, New York works as a slower alternative in the same state, but it is a separate trip rather than a swap inside a 7-day plan. Swap Washington for Boston if colonial history and seafood beat monuments; both are walkable and both connect to New York by train.

The canyon loop runs Las Vegas 1 night, Zion (Springdale) 2, Bryce Canyon 1, Page 2, Grand Canyon South Rim 2 and Las Vegas 2. That is 10 nights, not 7: it does not fit a one-week trip without cutting two stops.

It is a driving trip with long, empty stretches; fill the tank when you can. A non-resident annual parks pass (US$250 — check) pays off here because Zion, Bryce and Grand Canyon all charge an entrance fee.

With only 10 days, cut one stop rather than shortening every stop: two nights in a park is the minimum that feels like a visit.

The California classic runs San Francisco 3 nights, Yosemite 3, Monterey or Carmel 2, Santa Barbara 2 and Los Angeles 4 — 14 nights. It is a one-way car hire: pick up in San Francisco, drop in Los Angeles. Check Highway 1 closures and Yosemite reservation rules before you book anything else, because both can change the route.

The canyon loop is a 10-night route. To fill two weeks, add two nights at Zion or the Grand Canyon rather than adding a new region, and keep one buffer day for weather or road closures (check).

Both shapes work at 14 nights. If you have only 10, run the canyon loop as listed or cut California to San Francisco, Yosemite and Los Angeles.

Three weeks is enough for two regions if you accept one internal flight and one slower day after it. The supported building blocks are the 7-night Northeast train route and the 10-night canyon loop; pairing them gives about 17 nights, leaving the rest for travel days and a buffer.

A California classic (14 nights) plus the canyon loop (10 nights) is more than three weeks, so treat that pairing as an option to plan rather than a fixed route: cut one coast or one park stop to fit (check).

Keep each half around ten nights. Book the internal flight before the hotels, because the flight date decides everything else. Add a rest day after the flight rather than scheduling a park the same afternoon.

If you want a third region, drop a city rather than a park. Cities compress well; parks do not, because the driving is the point.

Book in this order: park lodging, then internal flights, then long-distance trains, then city hotels, then car hire. Park beds are the scarcest item and the one that reshapes the route. Separately, check whether the parks and dates on your route require a timed-entry reservation — some do and some do not, and the rule changes by park and season.

Trains and flights inside the country are covered on the getting-around page; entry rules on the visa page. Budget for tipping and taxes, which are added at the till in much of the country. Carry a card: many places are cashless, and small park businesses may not take foreign cards.

The most common error is treating the map as small. Three cities in seven days means three airport days and no city seen properly. The second is driving a route that should be a flight: coast-to-coast driving is a separate trip of its own, not a leg.

The third is booking flights before park lodging. If Yosemite or Grand Canyon lodging is full, the whole route shifts. The fourth is ignoring season: a June desert loop and a January Yellowstone plan both fail on heat or snow.

Finally, do not skip the return leg. One-way car hires and open-jaw flights need checking early, because the cheap version of a route is often the one that ends where it started.