The Kerimäki Church is the largest wooden church in the world. Designed by Anders Fredrik Granstedt and built between 1844 and 1847, the church has a length of 45 metres (148 ft), a width of 42 m (138 ft), a height of 37 m (121 ft) and a seating capacity of more than 3,000. Altogether there can be 5,000 people at a time in the church.
It has been rumoured that the size of the church was the result of a miscalculation when it was built (supposedly the architect was working in centimetres, which the builder took to be inches, which are 2.54 times larger). Further studies, however, have shown that the church was actually intended to be as big as it is, so it could easily accommodate a half of the area's population at the same time.
During wintertime, services are held in a smaller "winter church" (built in 1953), since the main building has no heating.
Reference: Wikipedia
The Broch of Clickimin is a large and well preserved, though somewhat restored broch near Lerwick. Originally built on an island in Clickimin Loch (now increased in size by silting and drainage), it was approached by a stone causeway. The water-level in the loch was reduced in 1874, leaving the broch high and dry. The broch is situated within a walled enclosure and, unusually for brochs, features a large 'blockhouse' between the opening in the enclosure and the broch itself. Another unusual feature is a stone slab featuring sculptured footprints, located in the causeway which approached the site. Situated across the loch is the Clickimin Leisure Centre.