| Biržai Regional Park | |
| Map: | Lithuania |
| Relief: | 1 |
| Location: | Panevėžys County, Lithuania |
| Nearest City: | Biržai |
| Coordinates: | 56.201°N 24.659°W |
| Area: | 14659ha |
| Established: | 1992 |
Biržai Regional Park covers 14659ha in northern Lithuania near its border with Latvia. It was established in 1992 to preserve a distinctive karst landscape. About 20% of its area is covered by forest.
The park is notable for its sinkholes, created by the dissolution of the gypsum underlying its soil. About 9,000 sinkholes have been identified; the most notable is the Karvės ola (Cow's Cave), which is about 20 meters deep.[1] In 1998 the use of pesticides and fertilizers in the area was restricted.