When to go

Best time to visit a national park

Not a vibe. A month table: heat, crowds, and whether it works with kids. Pick September if you can. Pick the row that matches the week you actually have, then open the trip as a poster.

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  April, May, September, and October

  Grand Canyon

  Arizona · from Phoenix, AZ

  September and October are the months to aim for on the South Rim: cooler hiking and lighter crowds than July. April and May are the spring version. Summer is packed, and the inner canyon is dangerously hot — stay on the rim with kids.

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  April, September, and October

  Zion

  Utah · from Las Vegas, NV

  September and October are the usual answer: still warm, fewer people after Labor Day, and the Narrows is usually in. April is the spring pick if you can live without the Narrows (snowmelt). July and August work only if you start at dawn and expect 100°F in the canyon.

Plan a trip from home How many days