The road to your dreams isn’t always easy to navigate, sometimes dotted with mountains to climb, obstacles to overcome—and hard, mind-numbing times that will make you feel like quitting. Just remember this if you get lost along the way: Anything worth having doesn’t come easy. So don’t turn back around. Don’t give up.

As you work to achieve your most ambitious goals, push yourself to keep moving forward with these 17 motivational quotes.

Related: Top of Mind: 7 Ways to Boost Self-Motivation

1. “Believe in yourself! Have faith in your abilities! Without a humble but reasonable confidence in your own powers you cannot be successful or happy.” —Norman Vincent Peale

3. “Where there is a will, there is a way. If there is a chance in a million that you can do something, anything, to keep what you want from ending, do it. Pry the door open or, if need be, wedge your foot in that door and keep it open.” —Pauline Kael

4. “Do not wait; the time will never be ‘just right.’ Start where you stand, and work with whatever tools you may have at your command, and better tools will be found as you go along.” —George Herbert

5. “Press forward. Do not stop, do not linger in your journey, but strive for the mark set before you.” —George Whitefield

7. “Aim for the moon. If you miss, you may hit a star.” —W. Clement Stone

8. “Don’t watch the clock; do what it does. Keep going.” —Sam Levenson

9. “There will be obstacles. There will be doubters. There will be mistakes. But with hard work, there are no limits.” —Michael Phelps

10. “Keep your eyes on the stars, and your feet on the ground.” —Theodore Roosevelt

11. “We aim above the mark to hit the mark.” —Ralph Waldo Emerson

12. “One way to keep momentum going is to have constantly greater goals.” —Michael Korda

13. “Change your life today. Don’t gamble on the future, act now, without delay.” —Simone de Beauvoir

14. “You just can’t beat the person who never gives up.” —Babe Ruth

15. “Start where you are. Use what you have. Do what you can.” —Arthur Ashe

16. “Why should you continue going after your dreams? Because seeing the look on the faces of the people who said you couldn’t… will be priceless.” —Kevin Ngo

17. “Never give up, for that is just the place and time that the tide will turn.” —Harriet Beecher Stow

Related: 19 Quotes About Motivation