I was impressed by a six hundred year old former cod-salting wharfside building in Bergen, Norway. Most of the original wood was intact and accessible - you could touch the old tool marks. The building now houses a mere motorcycle dealership, which is pretty mind boggling for an American. The bike salesmen thought I was pretty odd.
Water is the enemy of wood and can rot it pretty quickly as well as invite termites. If wood is kept dry, it will last nearly forever. There is some ancient Egyptian furniture in museums that is more than 2,000 years old, and even more furniture and wooden artifacts (shields, tools, etc.) that are more than 1,000 years old.
