Convenient Enemy Base

As the saying goes, opposites attract; heroes and villains have a natural tendency to draw their opposites to themselves. Nowhere is this more clearly demonstrated than in the Convenient Enemy Base: If the heroes crash-land or shipwreck while on a mission against a powerful enemy, they will almost always wash up no more than a mile or two from that enemy's camouflaged and hidden headquarters. The heroes, after coming to, will then automatically and unknowingly walk directly toward its main entrance, even if they're trying to go anywhere but.

Often a consequence of It's a Small World After All.

Anime and Manga

 * In Nadia: The Secret of Blue Water, Nadia and/or her friends end up unwittingly sitting on top of enemy installations twice in the course of the show.
 * On the other end of the spectrum, the protagonists of Saiyuki, the Genjo Sanzo party, have been attempting to get to the enemy base for the entirety of Gensou Maden Saiyuki and Saiyuki Reload, but have not yet reached it (mainly due to a great deal of interference from various gods and demons). Meanwhile, the main antagonists, Kougaiji's group, fly back and forth between the base and wherever the Genjo party happens to be time and time again.

Comic Books

 * In one X-Men story, Cyclops gets shipwrecked onto an island; by purest coincidence it turns out to be the base of X-Men adversary Magneto, who is just about to enact a plan to take over the world.

Film

 * In the movie GoldenEye, James Bond flies over a lake in Cuba looking for Janus's secret base. He's just about to give up when a missile shoots him down. After The Dragon sent to finish him off gets killed, Janus thoughtfully drains the lake, revealing the base.
 * Not exactly an enemy base, but in the Tenacious D movie, JB randomly journeys around a forest after consuming wild mushrooms with psychedelic effects, but when he comes to (after a big fall), he is conveniently close to his target (the Rock N' Roll Hall of Fame).
 * Teal'c ending up within walking distance of the Ori base in Stargate: The Ark of Truth.
 * Technically justified since.
 * It is also showed to be a really long walk. They had a walking montage and everything!

Live Action TV

 * This is part of how the Doctor operates on Doctor Who: he always seems to end up somewhere with something interesting happening, although it's implied he and his companion(s) go other places offscreen.
 * The TARDIS seems curiously attracted to whatever interplanetary incident happens to be most dramatic, especially when the Doctor's looking for a break.
 * In the serial Genesis of the Daleks the Kaleds and the Thals have been fighting an internecine war for control of the planet Skaro for thousands of years and yet their two massive domed cities are seemingly about a half-mile apart. Well, who wants to walk a long way to a battle?
 * In The Doctor's Wife, it is explicitly stated that the TARDIS takes him exactly where he needs to go.

Video Games

 * Knights of the Old Republic II is probably the king of this trope, as the player's ship manages to crash-land near a conveniently-placed (and always secret) base no less than four times. Two out of these four times, though, it's not the enemies, but more of a neutral side that chooses not to interfere.
 * This was partly subverted in the first game when the player's ship crash lands on the exact spot they need to get to... because that's where the machine that sucks spaceships on to the surface is.
 * Hang on... Czerka base on Telos, Telos Academy, Dxun, and Malachor V? Excessive though it is, the Telos Academy probably doesn't count, considering that you'd just figured out its location and been travelling there when shot down by a third party not affiliated with the academy.
 * In Command And Conquer: Renegade, Captain Nick "Havoc" Parker gets shot down after hijacking a plane from a Nod airstrip. He grabs a parachute, jumps out, and lands right on a conveniently placed beachhead that leads to a convenient enemy base.
 * In Star Ocean: The Last Hope, the ship gets sucked into a black hole, spat out over 1957 Earth and makes an emergency landing...right on top of the local alien-experimenting military agency's Elaborate Underground Base.
 * And for The Very Definitely Final Dungeon, the ship conveniently ends up crash landing within walking distance of the planet's control center and Final Boss therein.

Western Animation

 * In the G.I. Joe Shaggy Dog Story "The Viper is Coming", the Joes interpret part of the message to mean a set of coordinates. Even though the message turns out to mean something entirely different, when they check the location out, whaddaya know? There's a Cobra training camp right there!