Potomac River Run Marathon

Potomac River Run Marathon 2026 Course Analysis

Potomac River Run Marathon is a full marathon held in Washington, United States of America, scheduled for Saturday 2 May 2026. The course is run on mixed surface with 67m of total elevation gain, reaching a maximum altitude of 35m above sea level. For registration and full race details, visit the official Potomac River Run Marathon website.

Elevation Profile

This is a very flat course with only 67m of total elevation gain across the full distance. The course ranges from 11m to 35m above sea level — a 24m elevation range that makes it one of the flatter races available. Runners targeting a personal best will appreciate the minimal climbing.

Expected Race Day Weather

Based on historical weather data for May, the expected race day conditions are as follows. Hot conditions are expected, with temperatures between 20°C and 29°C. Heat is one of the biggest performance factors in marathon running — research shows that for every degree above 15°C, marathon times slow by approximately 1-2%. Extra hydration and a conservative start are strongly recommended. There is a moderate chance of rain (23%). Runners may want to prepare for wet conditions but shouldn't expect persistent rainfall.

Surface Type: Mixed

Potomac River Run Marathon features a mixed-surface course, combining sections of road with unpaved terrain such as gravel paths, parkland, or boardwalks. Mixed courses add variety but also introduce some unpredictability in footing. Runners should expect slightly slower times compared to a pure road marathon, and road-trail hybrid shoes may be the best footwear option.

How Difficult Is Potomac River Run Marathon?

Our difficulty rating for Potomac River Run Marathon is calculated using a model that combines elevation gain, temperature impact, and surface type. Use the difficulty calculator above to enter your target finish time and see exactly how many minutes this course would add or subtract compared to a perfectly flat, cool, road-based marathon. Faster runners and slower runners are affected differently by the same course conditions, so the difficulty is personalised to your pace.

Looking for an easier marathon or a tougher challenge? You can also compare Potomac River Run Marathon against other marathons to find the right race for your goals.