Cave lovers are being given the chance to snap up a set for £150,000 which includes a seven-mile underground network.
The five limestone caves are hidden away under 2.5 acres of woodland in Wales.
While they'd be ideal for someone who loves to explore caves they could also be turned into an underground home if the new owner is granted planning permission.
It's located at the foot of the Great Forest hills in the Brecon Beacons national park and dates back half a million years.
The current owner of the site is a local farmer who has put it up for sale which through Rightmove.
Experts say it could as a private property or be utilised for commercial purposes so could offer outdoor activities for nature fans.
Simon Edwards, from McCartneys estate agents in Hay-on-Wye, told Metro : "As you can imagine, the cave market isn’t always particularly buoyant, but we’re thrilled to have been instructed on this listing."
The site has many parts that have yet to explored and there are also beautiful surrounding the space plus waterfalls and mountain views close by.
Buying agent Henry Pryor said it's ideal for an aspiring 'Fred Flintstone'.
Tim Bannister, of Rightmove, added: "It’s not every day that we’re able to share such a unique and quirky listing with the world, but this remarkable plot of land has certainly captured the team’s attention.
"For the same price as a Kensington car park space, you can buy 2.5 acres of serene woodland and spend your weekends exploring more than seven miles of your very own underground cave network."