lava tubes really pretty spectacular?
This is the challenge with sensitive cave habitats. Only 1 of the 3 caves systems are visitable, the one open to the public is certainly massive, striking, and unique, However, few would call it "pretty", the two other caves are extremely fragile and include a rare underground alkaline lake and a rare limestone cave fused with a lava tube system, quite spectacular. Based on the nomination file, it compares well with Hawaii Volcanoes NP's Lava Tubes and is generally considered more significant and outstanding as a Lava Tube system.
What makes Jeju special is the breadth of the nomination
. Habitat, Lava Tube System, Volcanic features (tuff cone, crater lake, oreums) Nevertheless, based on the truly exceptional qualities of the iconic sites already mentioned, Jeju may not make the cut, I just wanted to share some of the exceptional qualities of this natural site.
"Jeju Volcanic Island and Lava Tubes is a coherent serial property comprising three components. The unequalled quality of the Geomunoreum lava tube system and the exhibition of diverse and accessible volcanic features in the other two components demonstrate a distinctive and important contribution to the understanding of global volcanism." Advisory Body
"The flora at the Mt. Halla National Park is unique. 1,565 vascular plant species have been recorded in the area thus far and is the highest number of plants in any mountain, 33 which are endemic to the island. Unlike most other Korean mountain environments, Hallsan has a unique vertical distribution of plants in three different zones: the subtropic, temperate, and frigid zones." wiki
The summit/crater lake at Hallasan NP and the Ilchulbong Tuff cone certainly stand out as iconic within the East Asia sphere.