Complex sentence: A portion of the Interstate 5 was also constructed through the park in the 1950s, and, combined with the 163, both freeways take up 111 acres of land that had been initially designated for the park.
Split into simpler sentences: A portion of Interstate 5 was constructed through the park in the 1950s. In total, freeways take up 111 acres of land that had been initially designated for the park.