How Crowded Is Manhattan Project National Historical Park in March?

March runs about 0.9× Manhattan Project National Historical Park's average month, which makes it an average month here — roughly 8% of the park's yearly visitors come in March.

In a typical March the park sees roughly 5,100 recreation visits, based on National Park Service monthly counts from 2016 to 2025.

That makes March the 8th-busiest of the park's twelve months, sitting between the July peak (1.7×) and the January low (0.3×).

On our Best Time to Visit score March rates 31/100 ("Poor"), versus the top-rated May at 56/100 — pleasant weather with noticeably thinner crowds (shoulder season).

Typical March weather, from 1991–2020 NOAA climate normals at the nearest station, averages a daytime high near 53°F and an overnight low around 30°F, with about 1" of precipitation and roughly 6" of snow.

That average of about 42°F is cool, so layers and a shorter daylight window matter.

Because June, July and August together draw about 37% of annual visitors, choosing March instead steps outside that summer crush — the single biggest lever on how crowded the park feels.

You'll have about 11.7 hours of daylight in March to explore — between the 9.6-hour midwinter low and the 14.4-hour summer high.

Park-wide, 2025 drew 56,390 recreation visits, down 24.5% from 74,693 in 2024.

Across the past decade overall visitation has eased about 43.1%, so March may feel a touch quieter than it once did.