I'm trying to create a multi-day trip (which is already a terrible experience), but I found that I can't create a trip longer than 1609km. Why is it so restrictive? I'm trying to create a ~2300km, but the application blocks me from doing so

I'm trying to create a multi-day trip (which is already a terrible experience), but I found that I can't create a trip longer than 1609km. Why is it so restrictive? I'm trying to create a ~2300km, but the application blocks me from doing so

You are probably aware that 1609km is just fractionally less than 1000 miles. I guess there is some hard-coded limit in the planning code. Go to the Garmin suggestions area and ask if they will consider increasing the limit?
www.garmin.com/.../
Oh that makes sense! Thanks, I don't use miles as a measurement unit regularly but now it's clear why. I will take a look at the Garmin suggestions
I'm trying to create a multi-day trip
I do not think the feature is really designed to that. You can create an event of maximally 48 hours. If that is sufficient, then I recommend switching to the time-based event. If not, then create a series of multiple events. And as for courses - if you want to use it for the navigation, you'll have problems using any course longer than 100 or 200 km for cycling, or even much less for trails and hikes, where you need higher resolution. The device will reduce the number of course points (usually to 200), so long tracks would render with a very low resolution, skipping the majority of points. Splitting the complete itinerary into multiple shorter segments is the way to go.