TV Ratings: 13 Million Watch Nik Wallenda Cross Grand Canyon

As Sunday's massive social media response hinted, Nik Wallenda's tightrope crossing of the Grand Canyon proved a huge ratings draw for Discovery Channel. An average 8.5 million viewers tuned into Skywire Live, swelling to nearly 13 million during the actual walk.

Discovery offered no shortage of programming surrounding the actual walk, with the feat taking Wallenda 22 minutes and 54 seconds to complete, though it was the 9 p.m. hour that saw the biggest returns.

STORY: Tightrope Walker Nik Wallenda Successfully Completes Grand Canyon Walk on Live TV

From 9 to 9:10 p.m., the preshow averaged 6.25 million viewers, before rising to 10.68 million viewers for the main event (9:10 to 10:20 p.m.). It was during Wallenda's tense walk, 9:38 to 10:01 p.m., that the telecast hit its high with 12.98 million viewers. (Coverage began before the preshow starting at 8 p.m.)

Stunts like Wallenda's are proving to be a particularly bankable draw for Discovery. Simultaneously shattering YouTube records for lives streams, the network's December telecast of Felix Baumgartner's record-breaking skydive from the stratosphere brought Discovery record daytime ratings. Space Jump Live averaged 4.21 million viewers.

Skywire also brought a huge boost to Discovery newcomer Naked and Afraid. The clothing-free survivalist series delivered 4.16 million viewers after its solid lead-in, making it the network's biggest series launch since last year's Amish Mafia. The show also delivered a 2.8 rating with households and a 2.1 rating with adults 25-54.

Wallenda has been of particular interest to the news divisions of ABC and NBC. Last year, ABC News produced Wallenda's high-wire walk across Niagara Falls, which averaged more than 10 million viewers. That stunt -- which also took place on a Friday in June -- was promoted across the network with Good Morning America's Josh Elliott and ESPN's Hannah Storm anchoring live coverage from the falls.

This time, NBC News produced the Grand Canyon special with Today anchors Willie Geist and Natalie Morales on hand to provide play-by-play of Wallenda's latest stunt.

Marisa Guthrie contributed to this report.

Michael O'Connell