score:8
Rome2Rio is designed to do precisely this. It covers flights (even low-cost carriers), many trains and buses (both local transit and private long-distance buses), even some ferries and is able to combine them.
Icing on the cake is its ability to include some βdrivingβ (taxi/private car) to get to the closest train station or airport as necessary, whereas train or flight search engines try to connect stations/airports and not cities in their vicinity. So you can actually enter the name of two small villages and let it do its magic.
As far as I can tell, it strives to include at least one bus-based and one train-based solution for any request, together with various flight options and associated transit to reach the airports.
One limitation is that because it covers so much, it's difficult to know exactly how comprehensive it is or how it chooses between various potential solutions. The design also emphasizes simplicity over customizability so compared to a typical flight search engine, you don't have many options.
Upvote:7
As far as I know, Rome2Rio does this the best, although I don't often search this way - probably would have if the site existed when I lived in Europe...but I digress.
For example, if you want to go from Paris, France to Trogir, Croatia, without even specifying dates (although you can for prices), it shows a train + plane option, a train + bus option, and a drive option.
Bear in mind no site could show you EVERY option. Even assuming you could collate the literally thousands of ways you could go around from A to B in Europe (especially if you take the 'long' way), it just wouldn't make sense to display it that way. However, this seems to take the most logical ways in the various forms of transport, and presents them pretty well. As a result, it's the best I've seen.
(I have no affiliation with them)