For some, sim­ply par­tak­ing in extreme activ­i­ties is not enough — only the longest, fastest, most adren­a­line-pump­ing endeav­ors will suf­fice. If this label applies to you, here are a few under­tak­ings that are right up your alley.

Most Dan­ger­ous White­wa­ter Rapids
Any ‘most dan­ger­ous’ superla­tive is some­what debat­able, but the white­wa­ter rapids found in Ida­ho’s Lochsa Riv­er speak for them­selves. Dur­ing the 70-mile stretch between the towns of Pow­ell and Low­ell, rafters will encounter 63 dif­fer­ent rapids that are cer­ti­fied as Class III or high­er, many of which car­ry omi­nous names like ‘Ter­mi­na­tion’ or ‘Grim Reaper’. Rafters of all abil­i­ties are wel­come, but make no mis­take: only sea­soned pros with exten­sive rapids expe­ri­ence should ven­ture down the Lochsa.

Dead­liest Swell
The world is home to some tru­ly gnarly waves, from the teahupoo of south­ern Tahi­ti to the time-hon­ored Mav­er­icks of north­ern Cal­i­for­nia. But arguably the most dia­bol­i­cal swells, known col­lec­tive­ly as Cyclops, churn in the Esper­ance Coast off Aus­trali­a’s west­ern shore­line. Reach­able only by boat (which should be your first clue right there), Cyclops exhibits dra­mat­ic depth change that gen­er­ates vicious, oval-shaped bar­rels. The coast is also shal­low, so surfers that land the swell must con­tend with sharp patch­es of coral that reside on the ocean floor.

Cold­est Polar Bear Swim
We all know that every Polar Bear Swim is cold in its own right. That’s, uh, sort of the point. But if the typ­i­cal dip in Lake Michi­gan is too warm and relax­ing for your taste, con­sid­er a plunge in the North Pole. In 2007, an Eng­lish­man named Lewis Gor­don Pugh swam more than one kilo­me­ter in waters that reached a tem­per­a­ture of ‑1.7 degrees Celsius/29 degrees Fahren­heit. We’re not say­ing you have to com­plete a long-dis­tance swim — just the typ­i­cal can­non­ball will do. This is the North Pole.

High­est Bungee Jump
The Roy­al Gorge Bridge in Col­orado is the world’s high­est bungee-jump­ing spot by a mar­gin of near­ly 100 meters, but this thrilling plunge is rarely avail­able to cus­tomers as a ‘true’ bungee jump. So the hon­or of ‘world’s high­est com­mer­cial bungee’ goes to Chi­na — more specif­i­cal­ly, the Macau Tow­er. A New Zealan­der named Alan John Hack­ett set the Guin­ness World Record for his 233-meter jump in 2007, and aero­dy­nam­ic bungee enthu­si­asts are wel­come to take a stab at his record.

Largest Zipline
Locat­ed in seclud­ed Icy Strait Point near Hoonah, Alas­ka, the world’s largest zipline stretch­es more than a mile in length and drops more than 1,300 ver­ti­cal feet — not bad, for a 90-sec­ond excur­sion. Six rid­ers hit the line at once, and reach an top speed of 82 miles per hour before the ride is fin­ished. And like all great ziplines, the Icy Strait Point course offers a breath­tak­ing view — in this case, of the Alaskan coastal wilder­ness and miles of frigid seawater.

Bonus: Fastest Roller Coast­er
Those prone to motion sick­ness need not strap into the For­mu­la Rossa in Abu Dhabi, UAE. The world’s fastest roller coast­er reach­es a top speed of 240 kilo­me­ters an hour, and rid­ers are sub­ject­ed to 1.7 g’s of accel­er­a­tion. This ride is so extreme that those brave enough to ride must wear a set of pro­tec­tive gog­gles for the entire 2‑kilometer course track. Best of all — each pas­sen­ger car is designed to resem­ble a Fer­rari For­mu­la One model.