Lydia,
 
I don't know about Lejre, but there is an outstanding open air museum.   If
I remember correctly it is called the Frilandsmuseum just outside of Lyngby
north of Copenhagen a short ride on the S-train  (S-tog) from downtown.
 
It is huge - there are costumed caretakers and I do remember people in
skins.  But there are also manor houses, an underground house from the Faro
Islands, and many many others from the whole history of danish occupied
Scandinavia.   There are animals tended with respect to the era, and
gardens and fields also tended according to a given period.  It is truely a
wonderful place.
 
You should also plan to visit Trelleborg, on the western side of the
island.  It is a preserved viking rampart with a reconstructed  common
house.  It is truely fascinating.   Sometime ago here on museum-l there was
a discussion about miniature cities.  I refrained at the time, but now I
will mention that there was (and I hope still is) a model of medieval
Copenhagen, to scale, on the sidewalk somewhere near downtown (on the way
to the opera house I believe - a native could surely tell you).
 
Have a great time!
 
Suzanne Quigley
Detroit Institute of Arts
[log in to unmask]