NYPD drones, dogs, horses and helicopters will join throngs of spectators to keep a close eye on this year’s New York City Marathon, according to Police Commissioner Jessica Tisch.

While Tisch said there are “no known specific credible threats” to this year’s race, security across the city on marathon day is historically tight. Thousands of officers will be posted along the route, joined by specialized units on land, in the harbor and in the air. Strategically placed blocker vehicles will restrict access to busy areas, while intelligence teams will monitor live-feed cameras throughout the five boroughs, Tisch added.

“As always, there will be assets you will see and assets you will not see,” Tisch said.

The 50th New York City Marathon will begin, as always, with waves of runners crossing the Verrazzano-Narrows Bridge from Staten Island to Brooklyn. The 26.2-mile course weaves through Sunset Park, Park Slope and Williamsburg before crossing the Queensboro Bridge into Manhattan, where it takes runners along the Upper East Side. The course briefly crosses into the South Bronx, then returns to bring runners to the finish line in Central Park.