Koper Novigrad sul mare
Start from Koper and follow signs on the bike path to Izola, reach the coast which you follow to Izola, follow the coast through the harbor and climb up on asphalt to Jagodje, cross the campsite remaining high with a view of the sea, descend to the right on a very bumpy road, take (out of season) the scenic and technical Strunjan Peninsula trail, descend into the oasis and, on foot, cross the small bridges. You return to asphalt and climb to a path to the right just after a hairpin bend, which on easy trail leads to Paciugo, where on asphalt you climb back up and swoop down to Fiesa by the sea, to continue along the waterfront (again out of season) to climb back up to Piran, with spectacular views.
After the dutiful turn in the narrow streets, continue on asphalt toward Portoroz and at the second parking lot on the right follow the bike path that serves as a waterfront, to reach Portoroz. Continue south staying close to the sea, reaching the Sezza campground, after which you cross the new beach on grass and continue on asphalt into the dock. You skirt the salt pans of Lucia and immediately after the Croatian border the uphill dirt road begins on the right; follow the Parenzana until it would make a left turn, but instead continue straight along the coast on asphalt (possible variant to the right on the coast). One always keeps to the outermost road and at Savudrjia the real fun begins, on boardwalks and driveways on the beach, in and out of campsites, among kiosks and bathers.
Route of several dozen kilometers in pleasant ups and downs. The two largest towns are Umag and Novigrad, where the turnaround takes place. If you want to shorten the return trip, it is possible to go back up to Umag and cut to the right on uphill asphalt and then descend into ex-frontier, then follow the signs for the Parenzana, which saves several dozen km.