Be prepared to explore more muck and bones at the La Brea Tar Pits this summer. The Page Museum in the city's mid-Wilshire area will open two historic observation pits that contain fossils of saber-toothed cats, dire wolves, sloths, ancient bison and others, and add a new Excavator Tour this week to flesh out the story of L.A.'s Ice Age past.

The Observation Pit, built in 1952 by Henry Sims Bent, was the first fossil museum to open in the Hancock Park area. It reopens Saturday after being closed for several decades, according to the Page Museum, and will be part of a new Excavator Tour that takes visitors inside and outside. The pit highlights what hands-on scientists have been researching and discovering for more than a century.

The tar pits chronicle a time when beasts and birds traveled along what would become Wilshire Boulevard. Animals got stuck in the tar pit pool, still visible today at the museum, their bones trapped in the sticky goo that would prove to be a perfect preservative.

"The post-war gem was designed to engage visitors in the discovery of Ice Age fossils by allowing them to descend into an excavation pit. It was an important first step in the development of the park,” Jane Pisano, president and director of Natural History Museum, says in a statement. 

Observation Pit 91, which had been closed for seven years, also is reopening to the public. Visitors will be able to see fossils as they come out of the ground, so to speak, and understand more of the context around what the finds mean.

For example, what do the bones of wolves and cats tell us about their hunting habits? Can insect fossils shed light on climate change? The Excavation Tour also visits Project 23, which began fossil excavation in 2006 when the nearby Los Angeles County Museum of Art churned up more fossils (including the big mammoth nicknamed Zed) while working on an underground parking lot.

Excavator Tours operate 11:30 a.m., 12:30 p.m., 2:30 p.m. and 3:30 p.m. Mondays through Fridays, and 11 a.m., 1 p.m. and 3 p.m. on Saturdays and Sundays.

Museum admission and tour costs $12 for adults, $9 for seniors and students, and $5 for children 3 to 12 years old. Reservations are suggested; you select a date when buying an online ticket or make a reservation in person at the museum.

Info: Page Museum, (323) 934-7243