C++ Undefined Reference error between files

Question

I was coding a simple text based RPG when I came across this error. I use the Code::Blocks IDE, so it should compile it all for me. I'm new to C++ so I couldn't make sense out of all the rather advanced codes getting this same error. Here's the function it occurred in (home_action.cpp):

#include <iostream>
#include "header.h"

using namespace std;

void home_action()
{
    cout << "";
    cout << "\nYour health:  " << health;
    cout << "\nYour mana:  " << magic;
    cout << "\nYour gold:  " << gold;
    string mov;
    if (exp > 99)
    {
        cout << "\nRest to level up.";
    }
    else
    {
        cout << "\nYou have " << exp << "/100 exp.";
        string mov;
        cout << "\n"<< name << ", you're at home. Do you want to fight, travel, or steal some bread?  ";
        cin >> mov;
    }
    if (mov == "rest" and exp > 99)
    {
        level_up();
        home_action();
    }
    else if (mov == "fight")
    {
        combat_scene("Guard", 21, 70, 10, 5);
    }
    else if (mov == "stats")
    {
        cout << "\n" << strength << " strength.";
        cout << "\n" << intel << " intelligence.";
        cout << "\n" << sneak << " dexterity.";
        home_action();
    }
    else if (mov == "steal")
    {
        calculate_roll(sneak, 3);
        cout << "\n" << name << ", rolled a "<< die_roll << "!";
        if (goal > die_roll)
        {
            health = max_health;
            magic = max_magic;
            cout << "\n" << name << " stole a loaf of bread and restored health.";
            home_action();
        }
        else
        {
            cout << "\n" << name << " got into a fight!";
            combat_scene("Goblin", 12, 50, 5, 3);
        }
    }
    else if (mov == "quit")
    {
        cout << "\nYou took an arrow to the knee and decided to retire from adventuring.";
        cout << "Thanks for playing!";
    }
    else if (mov == "travel")
    {
        travel_locations();
        cout << "\nWhere do you want to travel to?";
        cin >> current_town;
        location();
    }
    else
    {
        cout << "\nYou cannot "<< mov << ".";
        home_action();
    }
}

This caused the following error:

||=== RPG, Debug ===|
obj\Debug\home_action.o||In function `Z11home_actionv':|
C:\Users\William\Documents\Stuff\Programming\C++\Randomness\RPG\home_action.cpp|64|undefined reference to `travel_locations()'|
C:\Users\William\Documents\Stuff\Programming\C++\Randomness\RPG\home_action.cpp|67|undefined reference to `location()'|
||=== Build finished: 3 errors, 0 warnings (0 minutes, 0 seconds) ===|

The header referenced is (header.h):

#ifndef HEADER_H_INCLUDED
#define HEADER_H_INCLUDED

#include <iostream>

using namespace std;

extern int intel;
extern int strength;
extern int sneak;
extern int damage;
extern int max_health;
extern int max_magic;
extern int enemy_health;
extern int health;
extern int magic;
extern string chosen_class;
extern int die_roll;
extern int goal;
extern int gold;
extern int exp;
extern string name;
extern string current_town;

void level_up();
void calculate_max();
void reset_healths();
void spell();
void attacking_turn();
void home_action();
void calculate_roll(int stat, int difficulty);
void combat_scene(string enemy, int xp_gain, int hp, int dmg, int money);
void location();
int main();
void travel_locations();


#endif // HEADER_H_INCLUDED

And the two functions mentioned in the error are here:

travel_locations():

#include <iostream>
#include "header.h"

using namespace std;

void travel_locations()
{
    if (current_town == "1" || current_town == "murthan")
    {
        cout << "\n2: Worthal";
        cout << "\n3: Einbron";
        cout << "\n4: Home";
    }
    else if (current_town == "2" || current_town == "worthal")
    {
        cout << "\n1: Murthan";
        cout << "\n3: Einbron";
        cout << "\n4: Home";
    }
    else if (current_town == "3" || current_town == "einbron")
    {
        cout << "\n1: Murthan";
        cout << "\n2: Worthal";
        cout << "\n4: Home";
    }
    else if (current_town == "4" || current_town == "home")
    {
        cout << "\n1: Murthan";
        cout << "\n2: Worthal";
        cout << "\n3: Einbron";
    }
}

location():

#include <iostream>
#include "header.h"

using namespace std;

void location()
{
    cout << "\n";
    if (current_town == "1" || current_town == "murthan")
    {
        murthan();
    }
    else if (current_town == "2" || current_town == "worthal")
    {
        worthal();
    }
    else if (current_town == "3" || current_town == "einbron")
    {
        einbron();
    }
    else if (current_town == "4" || current_town == "home")
    {
        cout << "\nYou have returned home.";
        home_action();
    }
    else
    {
        cout << "\nInvalid location. Enter another.";
        cin >> current_town;
    }
}

I cannot figure out what is causing this. Any help would be greatly appreciated.