Although the Museum is not currently open, general ticket information can be found at https://tarpits.org/plan-your-visit. Hancock Park is currently open for those who wish to visit the park while following safety measures put in place (social distancing, masks). If you'd like to visit the NHM Nature Gardens or Butterfly Pavilion, please visit nhm.org for more details.
I'd check their website once they reopen to the public, last time I checked it was around 15 for adults to get in, less for kids but La Brea Tar Pits still remain closed until further notice.
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