Over 25,000 runners took to Jerusalem’s streets Friday morning for the city’s annual marathon, shutting down roads across the capital to vehicular traffic.

This year’s run, which also includes a half-marathon and smaller runs, marks the fourth year the city is hosting the race, an event pushed by Mayor Nir Barkat, an avid runner who is himself participating.

During the run, a 20-year-old participant collapsed from heat stroke. He was rushed to Shaare Tzedek Medical Center in serious condition.

Fourteen other people were treated by paramedics for light injuries.

A number of schools around the capital were forced to cancel classes because of the run and drivers throughout the city were forced off main thoroughfares that serve as the route of the race. Roads were set to reopen by 2 p.m.

Some 26,000 people participated in the event, including 2,460 foreign runner from 54 countries, according to the city. The race day covers everything from the 42.2-kilometer full marathon to an 800-meter fun-run.

Gabriel Nile (Screen Capture: Channel 5)

Gabriel Nile (Screen Capture: Channel 5)

Ethiopian Gabriel Nile won the half-marathon with a time of one hour and 30 minutes.

Participants were greeted with sunny skies and slightly warmer than average temperatures.

The city’s hilly terrain make running there a challenge, locals say, a fact which has raised the profile of the annual marathon.

“It’s by far the hardest in Israel and one of the hardest in the world,” said Guy Gordon, a local Jerusalem marathon runner. “In marathon tourism, there’s the bucket list of the classic five and a few wild cards, and Jerusalem has become one of the wild cards.”

Spectators who prefer to leave their running shoes at home had plenty of spots to watch the race, which kicked off near Sacher Park in the city center just before 7 a.m.

The 10k began downtown, curved around the Old City, then along Hebron Road, down to King David Street, into Talbieh and Rehavia and then down to the finish line on Ben Zvi Boulevard. It was a similar, longer run for the half marathon, adding Emek Refaim and the German Colony, the train track park as well as a stretch toward East Talpiot, along the Tayelet overlooking the Old City, and over to Katamon before heading toward the finish line.

The full marathon started near the city’s museum row, headed into Hebrew University’s Givat Ram campus and then toward downtown, the Old City, King David Street, the German Colony, the train track park and over toward East Talpiot before heading back toward the finish line at Sacher Park.

In 2013, Abraham Kabeto Katale of Ethiopia set a course record of 2:16:29.