My wife and I will be travelling from the states to Berlin for a four day conference in September. My wife has seen Munich but I have never been to Germany or adjoining countries. We would like to arrive 4 days early to see more of Germany or a neighboring country.

We don't want to spend the whole time in a car or airport and are looking for suggestions. We enjoy small towns, scenery, day hikes and biking and are debating spending the extra four days using Berlin as a base for day trips vs. spending the time in another area.

Bavaria looks beautiful and Prague looks intriguing and fairly close but we are open to any suggestions. Ease of travel and time to get to Berlin would be a factor.

I'd stay around Berlin. Easily reached are Leipzig (superb) Dresden (one of my favourites). From Dresden Prague is very close - even more now that the highway goes the whole way.
Germans and others love to travel along the Elbe. I am not so familiar but have seen lots of bikers in Torgau - a charming small town but boring in the evening.
You could also find a wine tour there are sparkling wine quite good for in saxony.

i agree with WoinP.

Either stay in Berlin and do some day trips [very easy to get the train to Potsdam for example] or go to Dresden and use that as a base for touring that area - boat trips on the Elbe, the Bastei, Bad Schandau and little Switzerland, Meissen - even Prague.

In September it will be lovely.

"We would like to arrive 4 days early to see more of Germany...We enjoy small towns, scenery, day hikes and biking."

Spend Days 1,2,3 in the Middle Rhine Valley, just south of Koblenz - it's a UNESCO World Heritage site: http://whc.unesco.org/en/list/1066

Small towns... You'll find old-world villages dotting both sides of the river.

Bacharach:
https://upload.wikimedia.org/wikiped...arach_BW_9.JPG

Boppard:
Bikers taking a break in the main square - http://home.kpn.nl/JLKampen1961/alb/...%20Boppard.jpg
View from Boppard clifftop cafe - http://ext.pimg.tw/samlucky5711/1379...g?v=1379089585

St. Goar:
Rheinfels Castle- https://www.youtube.com/watch?x-yt-c...FF80wORNQ#t=32
View from the riverfront: http://www.schiffbilder.de/1024/pers...chen-18381.jpg
http://schnuggel-elsje.de/upload/Bilder/IMG_0131.JPG

Braubach:
Market square - https://c1.staticflickr.com/5/4143/4...d7071291_b.jpg
Marksburg Castle in Braubach: http://www.marksburg.de/en/

Oberwesel:
Town wall walk: http://www.oberwesel.de/en/wandern0/stadtmauerrundweg/

Oberwesel wine fest - http://www.oberwesel.de/uploads/pics/P1060485.JPG

(September is wine fest month. Good timing.)

Hike the Rhine Castle Trail (Rheinburgenweg): http://www.romantic-germany.info/index.php?id=2942

Biking: http://www.romantic-germany.info/things-to-do/cycling/

This is a very compact area. Trains provide service to all the towns on both riverbanks. Ferries (like the St. Goar ferry) get you back and forth. Day passes for trains run €20 - €30/per couple per day and allow mostly unfettered hopping on and off - they also cover ferry crossings.

The area is about 1 hour from FRA International airport.
When you leave on Day 4, it's about 6 hours to Berlin; you could leave as late as 3 pm and reach Berlin by 9 pm or so.

IMO, it also depends on whether your conference schedule leaves some time to explore Berlin or not.
If the conference was every day from 10-6, I'd stay in Berlin.
In case you travel on company expenses it may be worth to check if the rules let you travel to, for example, Munich or Frankfurt while the conference is in Berlin. If the rules said that you must go in/out Berlin, I'd also be leaning towards Dresden, river Elbe valley, Saxon Switzerland if you wanted something different in addition to Berlin. In addition, that area will not be so super crowded as the Rhine valley in September.

What the first two posters and Cowboy said. Dresden makes an excellent base and is only two hours from Berlin, so you don't lose much time going from the airport and back to your conference.

South of Dresden is the National Park Saxon Switzerland with bizarre sandstone patches, flat-top mountains, canyons, lovely villages and picturesque small towns. Cycling along the Elbe river and through the side valleys. There is hiking, free climbing, canoeing, horseback riding, paddle steamer trips on the river, spas ... You can visit castles, a spectacular fortress up on a flat-top mountain (Königstein). And you can hop across the border to the Czech Republic, the National Park Bohemian Switzerland offers similar scenery.

North of Dresden are vineyards (wine festivals in autumn), the picturesque town Meissen (with porcelain manufacture, castle, cathedral and old town worth seeing), moated Baroque chateau Moritzburg, an old narrow-gauge steam train and, and, and ...

And don't forget Dresden itself. World-class museums, churches, classical music/opera, quirky and vibrant district Neustadt with pubs, galleries, bars, ethnic food ...

I'd stay around Berlin, you can ride in amongst the lakes north of Berlin or, as others say take the bike path down to the Elbe and maybe Dresden

Just to start you off

http://berlinmap360.com/berlin-bike-map#.WSFhaXlFe00
http://bicyclegermany.com/elbe.html

Alternatively you might like a day out in Lubeck or Hannover rather than heading south