Our recommendation
Visit Manhattan Project in May
May offers pleasant weather with noticeably thinner crowds (shoulder season). For comparison, July is the most crowded month (~1.7× the average month) and January is the quietest.
Annual visits
56K
2025
Busiest month
Jul
1.7× avg
Quietest month
Jan
0.3× avg
10-yr trend
falling
-43.1%
How crowded is Manhattan Project by month?
Relative crowd level by month (1.0 = the park's average month), from NPS visitation records 2016–2025.
Month-by-month crowd, weather & daylight
| Month | Crowd level | Best-time score | Avg high / low | Daylight |
|---|---|---|---|---|
| January | Very quiet | 43 Poor | 40°F / 21°F | 9.8 h |
| February | Very quiet | 40 Poor | 45°F / 24°F | 10.7 h |
| March | Average | 31 Poor | 53°F / 30°F | 11.7 h |
| April | Average | 42 Poor | 61°F / 35°F | 12.9 h |
| May★ best | Busy | 56 Fair | 70°F / 44°F | 13.9 h |
| June | Busy | 61 Good | 81°F / 54°F | 14.4 h |
| July | Very busy | 51 Fair | 83°F / 57°F | 14.2 h |
| August | Busy | 59 Fair | 80°F / 55°F | 13.4 h |
| September | Busy | 56 Fair | 74°F / 49°F | 12.2 h |
| October | Busy | 39 Poor | 63°F / 38°F | 11.1 h |
| November | Quiet | 34 Poor | 50°F / 28°F | 10.1 h |
| December | Very quiet | 38 Poor | 40°F / 21°F | 9.6 h |
Climate normals (1991–2020) from the nearest NOAA station (USC00295084, ~1.6 mi away).
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About visiting Manhattan Project
Manhattan Project National Historical Park is a National Historical Park in NM, WA, TN and a relatively quiet park, drawing about 56,000 recreation visits in 2025. Visitation has eased over the past decade, down about 43.1%. Crowds concentrate sharply by season: July is the busiest month at about 1.7× the park's average month, while January is the calmest at roughly 0.3× — a 6-to-1 swing between high and low season. Roughly 37% of the year's visitors arrive in the three summer months of June, July and August alone, so timing a trip outside that window is the single biggest lever on how crowded the park feels. Weather swings from an average high-season warmth near 70°F in July down to about 30°F in January, with the wettest stretch in August. About 6 months a year see comfortable average temperatures in the 50–80°F range, which is part of why crowd timing and weather timing don't always line up. The sweet spot is May: pleasant weather with noticeably thinner crowds (shoulder season). Visit then and you trade a little peak-season certainty for noticeably shorter lines and easier parking than the July rush. Daylight ranges from about 9.6 hours in midwinter to 14.4 hours near the summer solstice, which shapes how much ground you can cover in a day. These crowd figures are drawn from 2016–2025 of National Park Service visitor-use records, paired with 1991–2020 NOAA climate normals, and are updated as new monthly data is released.
Park overview
The Manhattan Project is one of the most transformative events of the 20th century. It ushered in the nuclear age with the development of the world’s first atomic bombs. Most of this development took place in three secret communities located in Hanford, WA, Los Alamos, NM and Oak Ridge, TN. Today, you can visit these three sites that make up Manhattan Project National Historical Park.
Weather & conditions
The Manhattan Project National Historical Park has units in Hanford, WA, Los Alamos, NM, and Oak Ridge, TN. Check local weather conditions at each unit before you visit.
Park overview text courtesy of the National Park Service — official park site.
Where to stay near Manhattan Project
Hotels, cabins, lodges and vacation rentals near Manhattan Project National Historical Park — live availability and prices to plan your trip. May is our pick for the best balance of light crowds and good weather.
Top-rated places to stay near Manhattan Project
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Getting to Manhattan Project
The nearest airport is Albuquerque International Sunport (ABQ), about 98 mi (2 hr drive) away. Most visitors reach Manhattan Project by car.
Frequently Asked Questions
May offers pleasant weather with noticeably thinner crowds (shoulder season) at Manhattan Project National Historical Park. The park is busiest in July (about 1.7× the average month) and quietest in January.
July is the busiest month at Manhattan Project National Historical Park, running roughly 1.7 times the park's average monthly visitation.
January is the quietest month at Manhattan Project National Historical Park, at about 0.3× the average month — a good choice if you want to avoid crowds.
Manhattan Project National Historical Park recorded about 56,390 recreation visits in 2025. Visitation has been falling over the past decade (-43.1%).
Based on 1991–2020 climate normals, the warmest month at Manhattan Project National Historical Park averages about 70°F (July). See the month-by-month table above for the full picture.
Albuquerque International Sunport (ABQ) is the closest airport to Manhattan Project National Historical Park, about 98 mi (2 hr drive) away.
Nearby parks to visit
Keep exploring
Water quality of lakes near Manhattan Project
If you are planning to swim, paddle or fish on this trip, these graded lakes are within a 40-mile drive. Grades are A–F from EPA and state-agency sampling.
- Abiquiu Reservoir water qualityGrade A · 26 mi · NM
- Abiquiu Reservoir Chama R Inlet water qualityGrade A · 27 mi · NM
- Tribal Lake water qualityGrade — · 16 mi · NM
- Santa Cruz Lake water qualityGrade — · 22 mi · NM
- Fenton Lake water qualityGrade — · 24 mi · NM
Sources: National Park Service Visitor Use Statistics (2016–2025), NOAA NCEI U.S. Climate Normals 1991–2020. Crowd index = a month's visits ÷ the park's average month.