Garmin GPSMAP 640 Owner's Manual page 22

Marine Mode: Navigating
5. Touch Done to finish creating the route and to set the course, or
touch Cancel Route to delete the route.
Complete Route
Saving a Created Route (Route To)
You can save up to 50 routes, with up to 250 turns in each route.
1. After you create a route, touch
2. Touch Yes to save your current active route.
Following a Route (Route To) on the
Navigation Chart, Perspective 3D Screen, or
Mariner's Eye 3D Screen
After you create a route using Route to or choose a saved route
from the Where to? menu, a magenta and purple line appears
between the start point and the first turning point, then continues
on to each subsequent turning point. This magenta and purple line
represents the route leg (from turning point to turning point), and
does not move, even when you are off course.
16
Menu > Stop Navigation.
CAUTION

Even when you carefully create a route, legs may pass over land or
shallow water. Use visual sightings and steer to avoid land, shallow
water, and other dangerous objects.
When you are off course, an orange arrow appears to help steer you
back onto the route leg to the next turning point. This orange arrow
represents the Course to Steer.
1. After you create a route using Route To or choose a saved
route from the Where To? menu, from the Home screen, touch
Charts and then touch Navigation
Mariner's Eye 3D.
2. Follow the magenta and purple line (route leg) from the start
point to the first turning point.
3. After you reach the first turning point, follow the magenta and
purple line (route leg) to each subsequent turning point, until
you reach the end point.
4. Steer off course to avoid land, shallow water, and other
obstacles on the water.
GPSMAP 620 and GPSMAP 640 Owner's Manual
Chart, Perspective 3D, or