How Crowded Is Effigy Mounds National Monument in August?

August runs about 1.6× Effigy Mounds National Monument's average month, which makes it a busy month here — roughly 13% of the park's yearly visitors come in August.

In a typical August the park sees roughly 7,600 recreation visits, based on National Park Service monthly counts from 1979 to 2025.

That makes August the 2nd-busiest of the park's twelve months, sitting between the July peak (2×) and the December low (0.4×).

On our Best Time to Visit score August rates 58/100 ("Fair"), versus the top-rated May at 63/100 — pleasant weather with noticeably thinner crowds (shoulder season).

Typical August weather, from 1991–2020 NOAA climate normals at the nearest station, averages a daytime high near 81°F and an overnight low around 61°F, with about 4.2" of precipitation.

That average of about 71°F is a comfortable range for hiking and being outdoors all day.

August falls inside the park's busiest stretch: June, July and August together pull about 42% of the year's visitors, so a visit this month means sharing the park with the peak-season crowd.

You'll have about 13.8 hours of daylight in August to explore — between the 8.8-hour midwinter low and the 15.2-hour summer high.

Park-wide, 2025 drew 56,912 recreation visits, down 8.2% from 61,975 in 2024.

Across the past decade overall visitation has risen about 7.1%, so a August visit is likely to feel busier than it did a few years ago.