Dr.Richard Thompson, in Alien Identities, presents the idea of reaching other relams from certain locations on or in the Earth. This reminds me of the books Etidorhpa and Alice in Wonderland, where other realms were reached from points within the Earth's shell. In those realms, of course, a different set of physics was in vogue- activity seems to have shifted up to the astral plane or something like that. The nature and frequency of the particles in those cavern worlds seem to imbue the bodies of the visitors to those realms, such that the visitors may attain to and experience on the given plane.
Here is one Celtic tale from Alien Identities:
Now for some actual legends reproduced starting from page 300 of Alien Identities:
" Here is a traditional Celtic story in which the abduction theme is combined
with a visit from another world. The Sidhe-king Manannan Mac Lir once got
tired of his wife Fand, and she went to Ireland with her sister Libian with
the hope of marrying the hero Cuchulainn. They took the form of to birds and
rested on a lake in Ulster where Cuchulainn could see them while hunting.
The hero tried to capture them but failed, and feeling depressed by this, he
sat down by a menhir ( megalithic stone monument ) and went to sleep. Then
he saw two women, dressed in green and crimson cloaks, who alternately
struck him with a whiplike object. After this, he took to his bed with a
strange illness that no Druid or doctor in Ireland could cure.
For a year, Cuchulainn lay sick without speaking to anyone. Then an unknown
messenger came to him and sang a song promising to cure him of his malady if
he would accept the invitation of the daughters of Aed Abrat to visit them
in the other world. He returned to the place where he had taken sick and
again saw the woman with the green cloak. She identified herself as Libian
and asked him to go with her to the Plain of Delight to fight Labraid's
enemies. She promised him that as a reward he would obtain Fand as his wife.
In due course, he did this, overthrew Labraid's enemies, and remained in the
other world with Fand for a month. Then he returned to Ireland and
immediately got into trouble with his wife Emer, who was exceedingly jealous
of Fand. Emer obtained from the Druids a drink that caused Cuchulainn to
forget all about the otherworld, and Manannan Mac Lir decided to take back
Fand. Thus Cuchulainns's abduction into the realm of Sidhe was relatively
brief.
The otherworld of the Celts has various names, such as Avalon, Tir na nog
( Land of Youth ) and Plain of Delight. Examination of the stories makes it
clear that this realm would have to exist in a higher dimension. To reach
it, one must go to the right place in a three-dimensional space, and then
one must travel in a mystical fashion that we do not understand. We can speak
of this as an extra dimension of travel in to the three we are familiar
with.
Since the other world can be reached by mystical travel from this world, we
can speak of it as a parallel reality. This idea can be understood by
imagining jumping back and forth between two parallel planes which are close
together. The planes represent the parallel realities, and the jumping
corresponds to the higher-dimensional travel. "
Members-
There is more along these lines in Underground Abductions- Whereto?