Wood type? Restoring panels / stairs / banisters

Hi everyone, I tried to post this question last night but it didn’t go through, so I’m trying again (sorry if it shows as a double post somehow). We are in the process of stripping and hopefully restoring some wall panels / stairs / banisters. After stripping the varnish we found a brown reddish tone wood underneath (see attached photo). Can anyone identify what type of wood this is? We applied a second application of stripper but it remains the same (no wood stain has lifted) so can we assume this is the bare wood? Thanks for any kind responses!