How do I clear old destinations from maps

Rgurgo,

Select: Maps, Recents, and tap Clear, will delete all of the entries.

Select: Maps, Bookmarks, swipe right over the entry you wish to delete, and tap Delete...

The trick is to ensure you create a Bookmark for those locations you are likley to revisit, even infrequently.

Then you can rebuild the Route quickly, next time.

In this early version of Maps, the search may not locate your destination properly.

For example: Search for Perth Airport, Western Australia, will attempt to put you on the Arrivals Apron, not the Terminal.

The trick is to drop one pin at each Terminal, International and Domestic, label them neatly, for use on the current trip, and in future.