In the Cinque Terre there are over 110 km of trails by the sea, among the vineyards, in the woods, and it may happen that for a few days one or some paths are closed.
The easiest way to check if a path is open or if it is not accessible, is to check the situation on the Cinque Terre National Park website.
The indications on the Park website are very clear and provide an immediate perception of the situation on this web page.
You will find a beautiful map with the representation of all the trails in the REL network (Ligurian Hiking Network) in the Park area with a very easy perception of the difficulty of the path (tourist, hiking, expert) and of any closure, represented in black.
The same page contains many other interesting information including indications on hiking itineraries around each of the five towns (ring routes), the link to the PN5T Web-App, advice and references for exploring the Marine Protected Area.
The photo is taken from the Cinque Terre National Park website