On the left of your Basecamp screen you have "On my computer" and then "My Collection". All your routes and waypoints are in My Collection so if that is selected and you have a lot of routes and waypoints it will be a very crowded screen. Under My Collection you should have Last Week and Last Month. Selecting them will remove everything from the map except recent waypoints and routes but this is how you SHOULD be using Basecamp.
Before adding any waypoints or routes start a new project by right clicking the blank space under My collection and selecting New List. Name the list whatever you want, e.g. 2016 Holiday. Now make sure you have THAT list selected before adding or modifying any waypoints and routes for your holiday. Everything you do will be shown in 2016 Holiday and My Collection and the individual items are shown lower down the left side of the screen. Anything in the 2016 Holiday can be selected and deleted from that list with the option to also delete it from My Collection or keep a copy there. If you no longer need your 2016 Holiday List you can delete it with the option to keep or delete the contents from My collection.
This is a really flexible system once you get used to using it as you can drag and drop items from one list to another. For example. When I start a 2016 Holiday list I may want to use some waypoints from my 2010 holiday so I just select the 2010 list and drag the items I want to 2016. I have one list which just has a file of over 30,000 European campsites so unless zoomed right in the waypoints obscure everything. When I have a route planned in 2016 I drag the route to the campsite list. Look at the end of the route with the campsite list open, find a suitable campsite and drag it to the 2016 list.
Once I have finished with 2016 I can remove the routes from the campsite list just to keep it tidy but they still exist in My Collection unless I specifically remove them from there.
I also have a Personal List which shows family, friends and other items I could need regularly. I may know where my daughter lives but not necessarily the best way to get there from an unusual start point.
