Scattered across the northern regions of California are a handful of the world’s oldest sequoias and giant sequoias, reaching into the sky like something out of Tolkien’s universe.

These colossal trees can reach over 300 feet tall and be 3,000 years old. Over time, their trunks have become wide enough that enterprising locals can hollow them out in half to create incredible walkable trees.

And what’s even more impressive about these otherworldly tunnels is that, despite having their bases hollowed out, some of these trees continue to grow and thrive.

The first walk-through tree was created in Tuolumne Grove in Yosemite National Park in 1875 to promote tourism, according to Amazing Planet, as visitors paid to pass under it. It was carved from a 2,500-year-old giant sequoia that had been struck by lightning and then cut down and stripped of its bark.

A trend that continues today is that vacationers cruised around the incredible structures in their vintage cars. As time went on, more hollowed out trees were created and tourists were charged to drive through the tunnels.

Today, drive-through trees are no longer created due to environmental concerns, but tourists can still enjoy the carefully preserved specimens, relics of another era of tourism, in California’s national parks.

The first of these step trees was created at Tuolumne Grove (pictured) in Yosemite National Park in 1875 to promote tourism.

The angled opening in the Shire driveway tree at Myers Flat supposedly formed naturally. Nowadays it has to be supported by cables.

Taken in the 1930s, the image above shows a car driving through the Wawona Tree in Yosemite National Park’s Mariposa Grove.

Step trees have been around since the 19th century. On the left is an image taken in 1880 showing a horse-drawn carriage going through the Wawona Tree, while on the right is a car going through the same tunnel in 1923.

The Wawᴏna tree was very well known. On the left is an updated photograph of President Theodore Roosevelt driving through the tree tunnel, while on the right is a man standing under the massive tunnel in 1890.

The Wawona Tree (in updated photos, left and right) fell in 1969 after a severe storm in the region. It is now known as the Fallen Tunnel Tree.

The Candelabra Tree in Leggett, about 180 miles north of the San Francisco Bay Area, is located within a privately owned grove. Its enormous tunnel was excavated in 1937.

The 2,400-year-old candelabra tree’s name comes from the way its branches supposedly hang like chandeliers (pictured left and right).

The Tuolumne Grove tree became a successful attraction, prompting other businessmen to dig up similar trees.

An updated image of the Wawona Tree showing tourists waiting outside as cars pass through its tunnel one by one.