This is a 220km hiking route in northern Germany.  Lots of information at the website:  https://www.heidschnuckenweg.de/

Traumpfad München-Venedig, Marienplatz in Munich – Markusplatz in Venice, 550 km

The very name sounds magic: Munich - Venice. Moreover, consider the famous start and finish: Mariënplatz and Markusplatz - two of Europe's most beautiful squares – and you will understand the popularity.

Submitted by Ethan Kennedy:

The Minong Ridge Trail is widely considered the toughest trail on Isle Royale National Park. At just under 28 miles, the trail follows the Minong Ridge on the north side of the island from Windigo to McCargoe Cove. The trail is also the least traveled trail on the island, so vegetation engulfs it. The later in the season, the more vegetation you will encounter. I would suggest attempting this trail in May or early June when the vegetation isn't up to your head. 

The official way marked coastal path around the Isle of Wight which is  about 70 miles long, and mostly trail, path & downland.  You do not have to close the loop by crossing the River Medina.

Quandary Peak (14,265') is a very popular hike near Breckenridge, Colorado.  The East Ridge route is described here: https://www.14ers.com/route.php?route=quan1&peak=Quandary+Peak