I only have time for a quick comment right now- but others will have more to say.

You really do not have time for all those places in just 20 days. When you subtract the travel getting to and from Europe and all that travel IN Europe you would end up with only about 14 or 15 days free to see an do things. So you either need to cut some destinations or add several days.

You can't possibly do that many places in 20 days. Cut back to maybe 4 venues -- end even that's a lot - and you've got a viable trip plan; otherwise, it's a mess.

my advice is the same as the others - cut back.

also you say that you are a budget traveller - IME the more moving about you do, the pricier it gets. it's not just the cost of the traveling, but having to re-orientate oneself in a new place takes up valuable time and money - you have to find that nice cafe with the reasonably priced coffee, the cheap and friendly bar, the cosy restaurant with the tasty fixed price menu - all over again.

I would suggest picking 3 or 4 places that are easy to move between [London - Paris by eurostar for example] and concentrate on those.

are you going by train as I presume and if so going to all those countries by train investigate some kind of railpass - some great sources for planning a rail trip IMO are www.seat61.com; www.ricksteves.com and www.budgeteuropetravel.com - download the latter's free and superb IMO European Planning & Rail Guide for lots of great rail-oriented itineraries in all those countries (http://www.budgeteuropetravel.com/id2.html).

to maximize time and save on hotel costs consider hopping any of zillions of overnight trains running across Europe - relocated from one country to another whilst sleeping! This is also a good way IME to meet other travelers doing the same thing on Europe's amazing IMO overnight trains.

What about London, Paris, Amsterdam? If you are a budget traveller, you may want to skip Switzerland-quite expensive. If it were me I would just do London and Paris. You can take day trips from both cities to see more of the country, but both have plenty to do and see without leaving.

We just spent 9 days just in Rome and the surrounding areas and didn't see everything....so I would advise you to scale back so you really can see what you are interested in and ENJOY it.

LONDON, PARIS, AMSTERDAM, BLACK FOREST, BRUSSELS SWITZERLAND, ROME AND VATICAN>

20 days not possible?

How about 3 days each in London, Paris and Amsterdam and Rome = 12 days

4 days in Switzerland = 16

2 days each in Brussels and Black Forest - but I would suggest ditching those two places - Brussels to many is very disappointing - a modern city with little old-world romance IMO and of many others here.

Black Forest sounds neat but is just another of many forests in Europe - and is a detour off your route.

add those 4 days into other places

But really I think comments that it is not possible to do OP's tentative trip in 20 days are not accurate - very possible - especially if they take overnight trains sometimes to relocated quickly across Europe - like from Amsterdam to Switzerland.

Agree with Palenq - it is absolutely possible - notwithstanding the usual chorus of negativity from those who take pleasure in criticizing a travel style that is different from their own.

One of the keys to weighing the value of advice is to see if the responder thinks it is valuable to "inform" the OP that it takes time to travel between stops (let's just all presume that people are bright enough to know that 3 nights in a location means that there will only be 2.5 days of sightseeing and that they won't be able to teleport to the next city - okay?) and that the more you move around the more travel costs.

I am not sure of your original listing of stops was meant to be in your desired traveling order, but I think this makes a better progression:

LONDON 3
AMSTERDAM 3
BRUSSELS 2
PARIS 3
BLACK FOREST 2
SWITZERLAND 3
ROME/VATICAN 3

Depending on fares, putting Paris after London might not be that much difference.

I have suggested less time in both Brussels and The BF for the same reasons voiced by Palenq. Should you decide that either of those places don't make your final cut, my suggestions is that the additional days should be added to London, Paris, Switzerland and Rome in any combination that rewards your interests the most.

For your consideration, Brussels could be visited for a few hours or even a half day while you travel between Paris and Amsterdam since it is almost always a via point in any train travel between them. The travel time is only about 3:15 hours and you can book a connection that allows you to stop in Brussels for the better part of the day. For example, you could depart Paris at about 08:00 stop over in Brussels for 7.5 hours and then continue on to Amsterdam, arriving at about 18:40. Shorter or longer stop overs can be booked.

If you are thinking of the Black Forest for expecting to find exceptional or unusual beauty, it might be a bit of a disappointment -check some online images galleries and travelogues to see if it matches your impression or interest. That interest might be better served by spending the extra time in the Swiss Alps - although you haven't indicated that it is the Alps you wish to visit.

Some of your decision will depend on when you plan to travel. I am thinking somewhere in between those who say it can't be done and those who say it can. Technically, you can see all on your list but you won't have time to enjoy much of it - too much racing around.

Consider London(5 days) Amsterdam (2 days), Paris (5 days) and Rome (including the Vatican - 5 days). The other 2 or 3 days will be spent traveling from place to place. It will be a somewhat rushed trip but you will see a lot. Alternatively, you could substitute some time in Switzerland for Rome. But as a budget traveler, you should be aware that the prices in Switzerland are high.

What are your interests? When are you going? Where are you traveling from? Be sure to book an open jaw flight - in to your first destination and home from your last. Happy planning.

Agree with Palenq - it is absolutely possible - notwithstanding the usual chorus of negativity from those who take pleasure in criticizing a travel style that is different from their own.>>

I don't think that you read Pal's post very thoroughly, Aramis - he actually suggests dropping Brussels and the Black Forest, and adding those days to the other places.

nor do I take pleasure in criticising other peoples' plans - no more than you do in invariably encouraging them to squeeze a quart into a pint pot.

Agree with Palenq - it is absolutely possible - notwithstanding the usual chorus of negativity from those who take pleasure in criticizing a travel style that is different from their own.> Pas moi but is what Aramis said - and I of course agree as you do.

I don't think that you read Pal's post very thoroughly, Aramis - he actually suggests dropping Brussels and the Black Forest, and adding those days to the other places.>

Me thinks you should re-read Aramis' post because he did say exactly that and also the quote you attribute to me was indeed from Aramis.

While it is physically possible to stop in 8 or 9 places in 20 days - it will not be inexpensive - the more you travel between cities the higher the cost - and Switzerland, esp is VERY expensive - and you will have very little time to see or do anything.

And while it's true that you can take trains at night - most of them are not "overnight trains" so you can sleep - but often you will have to change trains once or twice in the middle of the night.

Of your destinations Brussels is quite boring - other places in Belgium have much more to see and do, the Black Forest is mildly pretty, but boring compared to the Swiss Alps - and the Vatican is in the middle of Rome.

Suggest you have a look at some maps of europe and check out bahn.de for train schedules for the entire continent.

pal - i think you should re-read your own post - where do you state as follows:

<<notwithstanding the usual chorus of negativity from those who take pleasure in criticizing a travel style that is different from their own.>>?

also, you say to drop Brussels and the Black forest, Aramis suggests to limit the time there. but the main thrust of my post was to take him up on the remark above, which came from him, not from you.

unless you want to claim credit for it of course?

none of which is very helpful to the OP, who i suspect is quite capable of taking or leaving whatever any of us say, without the running critique from some, who not content with putting in their own suggestions, feel a compulsion to criticise others.

>> "none of which is very helpful to the OP"

The dearth of practical information in my original response shames me.

pal - i think you should re-read your own post - where do you state as follows:

<<notwithstanding the usual chorus of negativity from those who take pleasure in criticizing a travel style that is different from their own.>>?

the main thrust of my post was to take him up on the remark above, which came from him, not from you.>

annhig - I am not clear on what you are saying about me - that I said I said that remark - if I did it was a mistake - I clarified that that remark was aramis' and not mine - I do agree with the sentiment of the remark however but I would never aim it at you - one of Fodor's most consistently polite and non-judgmental posters IMO - but at plenty of others who often say things like "beyond crazy" - "totally nuts" - "like a forced march" etc rather than gently giving their own opinion - and yes opinion only. Cheers.

Pal -i think you've been at the paint-stripper again!

Aramis - you have just disproved the old canard that americans can't do irony - well done!

Darn it - I was so trying for "mordant"

And where is this duck who presumes to besmirch American wit?

Were I an American, I would be highly offended and seek to challenge said drake ( perhaps I presume to much?) to a duel. Well, okay a three-legged sack race instead - nothing involving water though.

drake ( perhaps I presume to much?) to a duel. Well, okay a three-legged sack race instead - nothing involving water though.>>

how about a [duck] egg and spoon race?

As with a water event, I thought that anything involving an egg might unfairly advantage the duck.

Ok Annhig - I'll duck that one about the paint.

That is the best one yet, Pal. Bravo